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  • How would I create this background effect?

    - by William
    What would you call the effect applied to the backgrounds in the Giygas fight of Earthbound, and the battle backgrounds in Mother 3? This is what I'm talking about. http://www.youtube.com/watch?v=tcaErqaoWek http://www.youtube.com/watch?v=ubVnmeTRqhg Now anyone know how I could go about this without using animated images, or using openGL?

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  • changing the intensity of lighten/darken on bitmaps using PorterDuffXfermode in the Android Paint class

    - by user1116836
    Ok my orignal question has changed. How do i change the intensity of how something like this is effected? DayToNight.setXfermode(new PorterDuffXfermode(Mode.DST_IN)); in my dream world it would have worked like this DayToNight.setXfermode(new PorterDuffXfermode(Mode.DST_IN(10))); the 10 being a level of intensity. An example would be if I had a flickering candle, when the candle burns bright I want the bitmaps I am drawing to the screen to retain their origanol color and brightness, when it flickers I want the bitmaps to be almost blacked out, and I want to darken the Bitmaps as the light dims. I have equations, timers and all that figured out, just not how to actually apply it to change the color/brightness. Maybe burning the images is what im looking for? I just want to change the lightness lol. I feel like using paint.setShader might be a solution, but the information in this area is pretty limited from what i have been able to find. Any help would be appreciated. edit: to be crystal clear, i am looking for a way to lighten/darken bitmaps as I draw them to the canvas

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  • I'm looking for a blend mode that gives 'realistic' paint colors. (Subtractive)

    - by almosnow
    I've been looking for a blend mode to (well ...) blend two RGB pixels in order to build colors in the samw way that a painter builds them (i.e: subtractive). Here are quick examples of the type of results that I'm expecting: CYAN + MAGENTA = BLUE CYAN + YELLOW = GREEN MAGENTA + YELLOW = RED RED + YELLOW = ORANGE RED + BLUE = PURPLE YELLOW + BLUE = GREEN I'm looking for a formula, like: dest_red = first_red + second_red; dest_green = first_green + second_green; dest_blue = first_blue + second_blue; I've tried with the commonly used 'multiply' formula but it doesn't work; I've tried with custom made formulas but I'm still not able to 'crack' how it should work. And I know already a lot of color theory so please refrain from answers like: Check this link: http://the_difference_betweeen_additive_and_subtractive_lightning.html

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  • GLSL - one-pass gaussian blur

    - by martin pilch
    It is possible to implement fragment shader to do one-pass gaussian blur? I have found lot of implementation of two-pass blur (gaussian and box blur): http://callumhay.blogspot.com/2010/09/gaussian-blur-shader-glsl.html http://www.gamerendering.com/2008/10/11/gaussian-blur-filter-shader/ http://www.geeks3d.com/20100909/shader-library-gaussian-blur-post-processing-filter-in-glsl/ and so on. I have been thinking of implementing gaussian blur as convolution (in fact, it is the convolution, the examples above are just aproximations): http://en.wikipedia.org/wiki/Gaussian_blur

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  • Using Ogre particle point billboards with shaders

    - by Jay
    I'm learning about using Ogre particles and had some questions about how the point type particles work. Q. I believe point type particles are implemented as a single position. Is one single vertex is passed to the vertex shader? Q. If one vertex is passed to the vertex shader then what gets sent to the fragment shader? Q. Can I pass the particle size to the shader? Perhaps with a custom parameter?

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  • GLSL compiler messages from different vendors [on hold]

    - by revers
    I'm writing a GLSL shader editor and I want to parse GLSL compiler messages to make hyperlinks to invalid lines in a shader code. I know that these messages are vendor specific but currently I have access only to AMD's video cards. I want to handle at least NVidia's and Intel's hardware, apart from AMD's. If you have video card from different vendor than AMD, could you please give me the output of following C++ program: #include <GL/glew.h> #include <GL/freeglut.h> #include <iostream> using namespace std; #define STRINGIFY(X) #X static const char* fs = STRINGIFY( out vec4 out_Color; mat4 m; void main() { vec3 v3 = vec3(1.0); vec2 v2 = v3; out_Color = vec4(5.0 * v2.x, 1.0); vec3 k = 3.0; float = 5; } ); static const char* vs = STRINGIFY( in vec3 in_Position; void main() { vec3 v(5); gl_Position = vec4(in_Position, 1.0); } ); void printShaderInfoLog(GLint shader) { int infoLogLen = 0; int charsWritten = 0; GLchar *infoLog; glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &infoLogLen); if (infoLogLen > 0) { infoLog = new GLchar[infoLogLen]; glGetShaderInfoLog(shader, infoLogLen, &charsWritten, infoLog); cout << "Log:\n" << infoLog << endl; delete [] infoLog; } } void printProgramInfoLog(GLint program) { int infoLogLen = 0; int charsWritten = 0; GLchar *infoLog; glGetProgramiv(program, GL_INFO_LOG_LENGTH, &infoLogLen); if (infoLogLen > 0) { infoLog = new GLchar[infoLogLen]; glGetProgramInfoLog(program, infoLogLen, &charsWritten, infoLog); cout << "Program log:\n" << infoLog << endl; delete [] infoLog; } } void initShaders() { GLuint v = glCreateShader(GL_VERTEX_SHADER); GLuint f = glCreateShader(GL_FRAGMENT_SHADER); GLint vlen = strlen(vs); GLint flen = strlen(fs); glShaderSource(v, 1, &vs, &vlen); glShaderSource(f, 1, &fs, &flen); GLint compiled; glCompileShader(v); bool succ = true; glGetShaderiv(v, GL_COMPILE_STATUS, &compiled); if (!compiled) { cout << "Vertex shader not compiled." << endl; succ = false; } printShaderInfoLog(v); glCompileShader(f); glGetShaderiv(f, GL_COMPILE_STATUS, &compiled); if (!compiled) { cout << "Fragment shader not compiled." << endl; succ = false; } printShaderInfoLog(f); GLuint p = glCreateProgram(); glAttachShader(p, v); glAttachShader(p, f); glLinkProgram(p); glUseProgram(p); printProgramInfoLog(p); if (!succ) { exit(-1); } delete [] vs; delete [] fs; } int main(int argc, char* argv[]) { glutInit(&argc, argv); glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA); glutInitWindowSize(600, 600); glutCreateWindow("Triangle Test"); glewInit(); GLenum err = glewInit(); if (GLEW_OK != err) { cout << "glewInit failed, aborting." << endl; exit(1); } cout << "Using GLEW " << glewGetString(GLEW_VERSION) << endl; const GLubyte* renderer = glGetString(GL_RENDERER); const GLubyte* vendor = glGetString(GL_VENDOR); const GLubyte* version = glGetString(GL_VERSION); const GLubyte* glslVersion = glGetString(GL_SHADING_LANGUAGE_VERSION); GLint major, minor; glGetIntegerv(GL_MAJOR_VERSION, &major); glGetIntegerv(GL_MINOR_VERSION, &minor); cout << "GL Vendor : " << vendor << endl; cout << "GL Renderer : " << renderer << endl; cout << "GL Version : " << version << endl; cout << "GL Version : " << major << "." << minor << endl; cout << "GLSL Version : " << glslVersion << endl; initShaders(); return 0; } On my video card it gives: Status: Using GLEW 1.7.0 GL Vendor : ATI Technologies Inc. GL Renderer : ATI Radeon HD 4250 GL Version : 3.3.11631 Compatibility Profile Context GL Version : 3.3 GLSL Version : 3.30 Vertex shader not compiled. Log: Vertex shader failed to compile with the following errors: ERROR: 0:1: error(#132) Syntax error: '5' parse error ERROR: error(#273) 1 compilation errors. No code generated Fragment shader not compiled. Log: Fragment shader failed to compile with the following errors: WARNING: 0:1: warning(#402) Implicit truncation of vector from size 3 to size 2. ERROR: 0:1: error(#174) Not enough data provided for construction constructor WARNING: 0:1: warning(#402) Implicit truncation of vector from size 1 to size 3. ERROR: 0:1: error(#132) Syntax error: '=' parse error ERROR: error(#273) 2 compilation errors. No code generated Program log: Vertex and Fragment shader(s) were not successfully compiled before glLinkProgram() was called. Link failed. Or if you like, you could give me other compiler messages than proposed by me. To summarize, the question is: What are GLSL compiler messages formats (INFOs, WARNINGs, ERRORs) for different vendors? Please give me examples or pattern explanation. EDIT: Ok, it seems that this question is too broad, then shortly: How does NVidia's and Intel's GLSL compilers present ERROR and WARNING messages? AMD/ATI uses patterns like this: ERROR: <position>:<line_number>: <message> WARNING: <position>:<line_number>: <message> (examples are above).

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  • GLSL subroutine not being used

    - by amoffat
    I'm using a gaussian blur fragment shader. In it, I thought it would be concise to include 2 subroutines: one for selecting the horizontal texture coordinate offsets, and another for the vertical texture coordinate offsets. This way, I just have one gaussian blur shader to manage. Here is the code for my shader. The {{NAME}} bits are template placeholders that I substitute in at shader compile time: #version 420 subroutine vec2 sample_coord_type(int i); subroutine uniform sample_coord_type sample_coord; in vec2 texcoord; out vec3 color; uniform sampler2D tex; uniform int texture_size; const float offsets[{{NUM_SAMPLES}}] = float[]({{SAMPLE_OFFSETS}}); const float weights[{{NUM_SAMPLES}}] = float[]({{SAMPLE_WEIGHTS}}); subroutine(sample_coord_type) vec2 vertical_coord(int i) { return vec2(0.0, offsets[i] / texture_size); } subroutine(sample_coord_type) vec2 horizontal_coord(int i) { //return vec2(offsets[i] / texture_size, 0.0); return vec2(0.0, 0.0); // just for testing if this subroutine gets used } void main(void) { color = vec3(0.0); for (int i=0; i<{{NUM_SAMPLES}}; i++) { color += texture(tex, texcoord + sample_coord(i)).rgb * weights[i]; color += texture(tex, texcoord - sample_coord(i)).rgb * weights[i]; } } Here is my code for selecting the subroutine: blur_program->start(); blur_program->set_subroutine("sample_coord", "vertical_coord", GL_FRAGMENT_SHADER); blur_program->set_int("texture_size", width); blur_program->set_texture("tex", *deferred_output); blur_program->draw(); // draws a quad for the fragment shader to run on and: void ShaderProgram::set_subroutine(constr name, constr routine, GLenum target) { GLuint routine_index = glGetSubroutineIndex(id, target, routine.c_str()); GLuint uniform_index = glGetSubroutineUniformLocation(id, target, name.c_str()); glUniformSubroutinesuiv(target, 1, &routine_index); // debugging int num_subs; glGetActiveSubroutineUniformiv(id, target, uniform_index, GL_NUM_COMPATIBLE_SUBROUTINES, &num_subs); std::cout << uniform_index << " " << routine_index << " " << num_subs << "\n"; } I've checked for errors, and there are none. When I pass in vertical_coord as the routine to use, my scene is blurred vertically, as it should be. The routine_index variable is also 1 (which is weird, because vertical_coord subroutine is the first listed in the shader code...but no matter, maybe the compiler is switching things around) However, when I pass in horizontal_coord, my scene is STILL blurred vertically, even though the value of routine_index is 0, suggesting that a different subroutine is being used. Yet the horizontal_coord subroutine explicitly does not blur. What's more is, whichever subroutine comes first in the shader, is the subroutine that the shader uses permanently. Right now, vertical_coord comes first, so the shader blurs vertically always. If I put horizontal_coord first, the scene is unblurred, as expected, but then I cannot select the vertical_coord subroutine! :) Also, the value of num_subs is 2, suggesting that there are 2 subroutines compatible with my sample_coord subroutine uniform. Just to re-iterate, all of my return values are fine, and there are no glGetError() errors happening. Any ideas?

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  • Using a single texture image unit with multiple sampler uniforms

    - by bcrist
    I am writing a batching system which tracks currently bound textures in order to avoid unnecessary glBindTexture() calls. I'm not sure if I need to keep track of which textures have already been used by a particular batch so that if a texture is used twice, it will be bound to a different TIU for the second sampler which requires it. Is it acceptable for an OpenGL application to use the same texture image unit for multiple samplers within the same shader stage? What about samplers in different shader stages? For example: Fragment shader: ... uniform sampler2D samp1; uniform sampler2D samp2; void main() { ... } Main program: ... glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D, tex_id); glUniform1i(samp1_location, 0); glUniform1i(samp2_location, 0); ... I don't see any reason why this shouldn't work, but what about if the shader program also included a vertex shader like this: Vertex shader: ... uniform sampler2D samp1; void main() { ... } In this case, OpenGL is supposed to treat both instances of samp1 as the same variable, and exposes a single location for them. Therefore, the same texture unit is being used in the vertex and fragment shaders. I have read that using the same texture in two different shader stages counts doubly against GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS but this would seem to contradict that. In a quick test on my hardware (HD 6870), all of the following scenarios worked as expected: 1 TIU used for 2 sampler uniforms in same shader stage 1 TIU used for 1 sampler uniform which is used in 2 shader stages 1 TIU used for 2 sampler uniforms, each occurring in a different stage. However, I don't know if this is behavior that I should expect on all hardware/drivers, or if there are performance implications.

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  • How do multipass shaders work in OpenGL?

    - by Boreal
    In Direct3D, multipass shaders are simple to use because you can literally define passes within a program. In OpenGL, it seems a bit more complex because it is possible to give a shader program as many vertex, geometry, and fragment shaders as you want. A popular example of a multipass shader is a toon shader. One pass does the actual cel-shading effect and the other creates the outline. If I have two vertex shaders, "cel.vert" and "outline.vert", and two fragment shaders, "cel.frag" and "outline.frag" (similar to the way you do it in HLSL), how can I combine them to create the full toon shader? I don't want you saying that a geometry shader can be used for this because I just want to know the theory behind multipass GLSL shaders ;)

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  • Shadowmap first phase and shaders

    - by KaiserJohaan
    I am using OpenGL 3.3 and am tryin to implement shadow mapping using cube maps. I have a framebuffer with a depth attachment and a cube map texture. My question is how to design the shaders for the first pass, when creating the shadowmap. This is my vertex shader: in vec3 position; uniform mat4 lightWVP; void main() { gl_Position = lightWVP * vec4(position, 1.0); } Now, do I even need a fragment shader in this shader pass? from what I understand after reading http://www.opengl.org/wiki/Fragment_Shader, by default gl_FragCoord.z is written to the currently attached depth component (to which my cubemap texture is bound to). Thus I shouldnt even need a fragment shader for this pass and from what I understand, there is no other work to do in the fragment shader other than writing this value. Is this correct?

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  • Differences in cg shader code for OpenGL vs. for DirectX?

    - by Cray
    I have been trying to use an existing library that automatically generates shaders (Hydrax plugin for Ogre3D). These shaders are used to render water and somewhat involved, but are not extremely complicated. However there seems to be some differences in how the cg shaders are handled by OpenGL and DirectX, more specifically, I am pretty sure that the author of the library only has debugged all the shaders for DirectX, and they work flawlessly there, but not so in OpenGL. There are no compiler errors, but the result just doesn't look the same. (And I have to run the library in OpenGL.) Isn't cg supposed to be a language that can freely use the exact same code for both platforms? Are there any specific known caveats one should know about when using the same code for them? Are there any fast ways to find what parts of the code work differently? (I am pretty sure that the shaders are the problem. Otherwise Ogre3D has great support for both problems, and everything is abstracted away nicely. Other shaders work in OpenGL, etc...)

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  • What is the most efficient way to blur in a shader?

    - by concernedcitizen
    I'm currently working on screen space reflections. I have perfectly reflective mirror-like surfaces working, and I now need to use a blur to make the reflection on surfaces with a low specular gloss value look more diffuse. I'm having difficulty deciding how to apply the blur, though. My first idea was to just sample a lower mip level of the screen rendertarget. However, the rendertarget uses SurfaceFormat.HalfVector4 (for HDR effects), which means XNA won't allow linear filtering. Point filtering looks horrible and really doesn't give the visual cue that I want. I've thought about using some kind of Box/Gaussian blur, but this would not be ideal. I've already thrashed the texture cache in the raymarching phase before the blur even occurs (a worst case reflection could be 32 samples per pixel), and the blur kernel to make the reflections look sufficiently diffuse would be fairly large. Does anyone have any suggestions? I know it's doable, as Photon Workshop achieved the effect in Unity.

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  • What are the factors that determine the default frequency of a shader call?

    - by user827992
    After i have been played for some days with various vertex and fragments shaders seems clear to me that this programs are called by the GPU at every and each rendering cycle, the problem is that I can't really quantify this frequency and I can't tell if is based on some default values or not because I don't have a big collection of hardware right now to do extensive tests. For what i know the answer could be really trivial like "it's the same of the refresh rate of your monitor", but i would like some good answers on that to be clear on this. For instance looks really odd to me that all the techniques used to control the amount of FPS that i have seen until now uses a call for the OpenGL function glutGet(GLUT_ELAPSED_TIME) to retrieve a value in ms about when the rendering started but I have to relies on the CPU to do the math. Why I can't set an FPS value in OpenGL if OpenGL clearly has a counter and a timer/clock? PS I'm referring to OpenGL 3.0+

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  • How to pass one float as four unsigned chars to shader by glVertexPointAttrib?

    - by Kog
    For each vertex I use two floats as position and four unsigned bytes as color. I want to store all of them in one table, so I tried casting those four unsigned bytes to one float, but I am unable to do that correctly... All in all, my tests came to one point: GLfloat vertices[] = { 1.0f, 0.5f, 0, 1.0f, 0, 0 }; glEnableVertexAttribArray(0); glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 2 * sizeof(float), vertices); // VER1 - draws red triangle // unsigned char colors[] = { 0xff, 0, 0, 0xff, 0xff, 0, 0, 0xff, 0xff, 0, 0, // 0xff }; // glEnableVertexAttribArray(1); // glVertexAttribPointer(1, 4, GL_UNSIGNED_BYTE, GL_TRUE, 4 * sizeof(GLubyte), // colors); // VER2 - draws greenish triangle (not "pure" green) // float f = 255 << 24 | 255; //Hex:0xff0000ff // float colors2[] = { f, f, f }; // glEnableVertexAttribArray(1); // glVertexAttribPointer(1, 4, GL_UNSIGNED_BYTE, GL_TRUE, 4 * sizeof(GLubyte), // colors2); // VER3 - draws red triangle int i = 255 << 24 | 255; //Hex:0xff0000ff int colors3[] = { i, i, i }; glEnableVertexAttribArray(1); glVertexAttribPointer(1, 4, GL_UNSIGNED_BYTE, GL_TRUE, 4 * sizeof(GLubyte), colors3); glDrawArrays(GL_TRIANGLES, 0, 3); Above code is used to draw one simple red triangle. My question is - why do versions 1 and 3 work correctly, while version 2 draws some greenish triangle? Hex values are one I read by marking variable during debug. They are equal for version 2 and 3 - so what causes the difference?

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  • Possible / How to render to multiple back buffers, using one as a shader resource when rendering to the other, and vice versa?

    - by Raptormeat
    I'm making a game in Direct3D10. For several of my rendering passes, I need to change the behavior of the pass depending on what is already rendered on the back buffer. (For example, I'd like to do some custom blending- when the destination color is dark, do one thing; when it is light, do another). It looks like I'll need to create multiple render targets and render back and forth between them. What's the best way to do this? Create my own render textures, use them, and then copy the final result into the back buffer. Create multiple back buffers, render between them, and then present the last one that was rendered to. Create one render texture, and one back buffer, render between them, and just ensure that the back buffer is the final target rendered to I'm not sure which of these is possible, and if there are any performance issues that aren't obvious. Clearly my preference would be to have 2 rather than 3 default render targets, if possible.

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  • How can I render a semi transparent model with OpenGL correctly?

    - by phobitor
    I'm using OpenGL ES 2 and I want to render a simple model with some level of transparency. I'm just starting out with shaders, and I wrote a simple diffuse shader for the model without any issues but I don't know how to add transparency to it. I tried to set my fragment shader's output (gl_FragColor) to a non opaque alpha value but the results weren't too great. It sort of works, but it looks like certain model triangles are only rendered based on the camera position... It's really hard to describe what's wrong so please watch this short video I recorded: http://www.youtube.com/watch?v=s0JqA0rZabE I thought this was a depth testing issue so I tried playing around with enabling/disabling depth testing and back face culling. Enabling back face culling changes the output slightly but the problem in the video is still there. Enabling/disabling depth testing doesn't seem to do anything. Could anyone explain what I'm seeing and how I can add some simple transparency to my model with the shader? I'm not looking for advanced order independent transparency implementations. edit: Vertex Shader: // color varying for fragment shader varying mediump vec3 LightIntensity; varying highp vec3 VertexInModelSpace; void main() { // vec4 LightPosition = vec4(0.0, 0.0, 0.0, 1.0); vec3 LightColor = vec3(1.0, 1.0, 1.0); vec3 DiffuseColor = vec3(1.0, 0.25, 0.0); // find the vector from the given vertex to the light source vec4 vertexInWorldSpace = gl_ModelViewMatrix * vec4(gl_Vertex); vec3 normalInWorldSpace = normalize(gl_NormalMatrix * gl_Normal); vec3 lightDirn = normalize(vec3(LightPosition-vertexInWorldSpace)); // save vertexInWorldSpace VertexInModelSpace = vec3(gl_Vertex); // calculate light intensity LightIntensity = LightColor * DiffuseColor * max(dot(lightDirn,normalInWorldSpace),0.0); // calculate projected vertex position gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex; } Fragment Shader: // varying to define color varying vec3 LightIntensity; varying vec3 VertexInModelSpace; void main() { gl_FragColor = vec4(LightIntensity,0.5); }

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  • 2d game view camera zoom, rotation & offset using 'Filter' / 'Shader' processing?

    - by Arthur Wulf White
    I wish to add the ability to zoom-in, zoom-out, rotate and move the view in a top-down view over a collection of points and lines in a large 2d map. I split the map into a grid so I only need to render the points that are 'near' the camera. My question is, how do I render a point A(Xp,Yp) assuming the following details: Offset of the camera pov from the origin of the map is: Xc, Yc Meaning the camera center is positioned on top of that point. If there's a point in Xc, Yc it is positioned in the center of the screen. The rotation angle is: alpha The scale is: S Read my answer first. I am thinking there is more optimized solution, thanks. My question is how to include the following improvement: I read in the AS3 Bible book that: In regards to ShaderInput, You can use these methods to coerce Pixel Bender to crunch huge sets of data masquerading as images, without doing too much work on the ActionScript side to make them look like images. Meaning if I am performing the same linear function on a lot of items, I can do it all at once if I use Shaders correctly and save processing time. Does anyone know how that is accomplished? Here is a sample of what I mean: http://wonderfl.net/c/eFp0/

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  • How can I use a Shader in XNA to color single pixels?

    - by George Johnston
    I have a standard 800x600 window in my XNA project. My goal is to color each individual pixel based on a rectangle array which holds boolean values. Currently I am using a 1x1 Texture and drawing each sprite in my array. I am very new to XNA and come from a GDI background, so I am doing what I would have done in GDI, but it doesn't scale very well. I have been told in another question to use a Shader, but after much research, I still haven't been able to find out how to accomplish this goal. My application loops through the X and Y coordinates of my rectangular array, does calculations based on each value, and reassigns/moves the array around. At the end, I need to update my "Canvas" with the new values. A smaller sample of my array would look like: 0,0,0,0,0,0,0 0,0,0,0,0,0,0 0,0,0,0,0,0,0 1,1,1,1,1,1,1 1,1,1,1,1,1,1 How can I use a shader to color each pixel?

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  • OpenGL 3.x Assimp trouble implementing phong shading (normals?)

    - by Defcronyke
    I'm having trouble getting phong shading to look right. I'm pretty sure there's something wrong with either my OpenGL calls, or the way I'm loading my normals, but I guess it could be something else since 3D graphics and Assimp are both still very new to me. When trying to load .obj/.mtl files, the problems I'm seeing are: The models seem to be lit too intensely (less phong-style and more completely washed out, too bright). Faces that are lit seem to be lit equally all over (with the exception of a specular highlight showing only when the light source position is moved to be practically right on top of the model) Because of problems 1 and 2, spheres look very wrong: picture of sphere And things with larger faces look (less-noticeably) wrong too: picture of cube I could be wrong, but to me this doesn't look like proper phong shading. Here's the code that I think might be relevant (I can post more if necessary): file: assimpRenderer.cpp #include "assimpRenderer.hpp" namespace def { assimpRenderer::assimpRenderer(std::string modelFilename, float modelScale) { initSFML(); initOpenGL(); if (assImport(modelFilename)) // if modelFile loaded successfully { initScene(); mainLoop(modelScale); shutdownScene(); } shutdownOpenGL(); shutdownSFML(); } assimpRenderer::~assimpRenderer() { } void assimpRenderer::initSFML() { windowWidth = 800; windowHeight = 600; settings.majorVersion = 3; settings.minorVersion = 3; app = NULL; shader = NULL; app = new sf::Window(sf::VideoMode(windowWidth,windowHeight,32), "OpenGL 3.x Window", sf::Style::Default, settings); app->setFramerateLimit(240); app->setActive(); return; } void assimpRenderer::shutdownSFML() { delete app; return; } void assimpRenderer::initOpenGL() { GLenum err = glewInit(); if (GLEW_OK != err) { /* Problem: glewInit failed, something is seriously wrong. */ std::cerr << "Error: " << glewGetErrorString(err) << std::endl; } // check the OpenGL context version that's currently in use int glVersion[2] = {-1, -1}; glGetIntegerv(GL_MAJOR_VERSION, &glVersion[0]); // get the OpenGL Major version glGetIntegerv(GL_MINOR_VERSION, &glVersion[1]); // get the OpenGL Minor version std::cout << "Using OpenGL Version: " << glVersion[0] << "." << glVersion[1] << std::endl; return; } void assimpRenderer::shutdownOpenGL() { return; } void assimpRenderer::initScene() { // allocate heap space for VAOs, VBOs, and IBOs vaoID = new GLuint[scene->mNumMeshes]; vboID = new GLuint[scene->mNumMeshes*2]; iboID = new GLuint[scene->mNumMeshes]; glClearColor(0.4f, 0.6f, 0.9f, 0.0f); glEnable(GL_DEPTH_TEST); glDepthFunc(GL_LEQUAL); glEnable(GL_CULL_FACE); shader = new Shader("shader.vert", "shader.frag"); projectionMatrix = glm::perspective(60.0f, (float)windowWidth / (float)windowHeight, 0.1f, 100.0f); rot = 0.0f; rotSpeed = 50.0f; faceIndex = 0; colorArrayA = NULL; colorArrayD = NULL; colorArrayS = NULL; normalArray = NULL; genVAOs(); return; } void assimpRenderer::shutdownScene() { delete [] iboID; delete [] vboID; delete [] vaoID; delete shader; } void assimpRenderer::renderScene(float modelScale) { sf::Time elapsedTime = clock.getElapsedTime(); clock.restart(); if (rot > 360.0f) rot = 0.0f; rot += rotSpeed * elapsedTime.asSeconds(); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT); viewMatrix = glm::translate(glm::mat4(1.0f), glm::vec3(0.0f, -3.0f, -10.0f)); // move back a bit modelMatrix = glm::scale(glm::mat4(1.0f), glm::vec3(modelScale)); // scale model modelMatrix = glm::rotate(modelMatrix, rot, glm::vec3(0, 1, 0)); //modelMatrix = glm::rotate(modelMatrix, 25.0f, glm::vec3(0, 1, 0)); glm::vec3 lightPosition( 0.0f, -100.0f, 0.0f ); float lightPositionArray[3]; lightPositionArray[0] = lightPosition[0]; lightPositionArray[1] = lightPosition[1]; lightPositionArray[2] = lightPosition[2]; shader->bind(); int projectionMatrixLocation = glGetUniformLocation(shader->id(), "projectionMatrix"); int viewMatrixLocation = glGetUniformLocation(shader->id(), "viewMatrix"); int modelMatrixLocation = glGetUniformLocation(shader->id(), "modelMatrix"); int ambientLocation = glGetUniformLocation(shader->id(), "ambientColor"); int diffuseLocation = glGetUniformLocation(shader->id(), "diffuseColor"); int specularLocation = glGetUniformLocation(shader->id(), "specularColor"); int lightPositionLocation = glGetUniformLocation(shader->id(), "lightPosition"); int normalMatrixLocation = glGetUniformLocation(shader->id(), "normalMatrix"); glUniformMatrix4fv(projectionMatrixLocation, 1, GL_FALSE, &projectionMatrix[0][0]); glUniformMatrix4fv(viewMatrixLocation, 1, GL_FALSE, &viewMatrix[0][0]); glUniformMatrix4fv(modelMatrixLocation, 1, GL_FALSE, &modelMatrix[0][0]); glUniform3fv(lightPositionLocation, 1, lightPositionArray); for (unsigned int i = 0; i < scene->mNumMeshes; i++) { colorArrayA = new float[3]; colorArrayD = new float[3]; colorArrayS = new float[3]; material = scene->mMaterials[scene->mNumMaterials-1]; normalArray = new float[scene->mMeshes[i]->mNumVertices * 3]; unsigned int normalIndex = 0; for (unsigned int j = 0; j < scene->mMeshes[i]->mNumVertices * 3; j+=3, normalIndex++) { normalArray[j] = scene->mMeshes[i]->mNormals[normalIndex].x; // x normalArray[j+1] = scene->mMeshes[i]->mNormals[normalIndex].y; // y normalArray[j+2] = scene->mMeshes[i]->mNormals[normalIndex].z; // z } normalIndex = 0; glUniformMatrix3fv(normalMatrixLocation, 1, GL_FALSE, normalArray); aiColor3D ambient(0.0f, 0.0f, 0.0f); material->Get(AI_MATKEY_COLOR_AMBIENT, ambient); aiColor3D diffuse(0.0f, 0.0f, 0.0f); material->Get(AI_MATKEY_COLOR_DIFFUSE, diffuse); aiColor3D specular(0.0f, 0.0f, 0.0f); material->Get(AI_MATKEY_COLOR_SPECULAR, specular); colorArrayA[0] = ambient.r; colorArrayA[1] = ambient.g; colorArrayA[2] = ambient.b; colorArrayD[0] = diffuse.r; colorArrayD[1] = diffuse.g; colorArrayD[2] = diffuse.b; colorArrayS[0] = specular.r; colorArrayS[1] = specular.g; colorArrayS[2] = specular.b; // bind color for each mesh glUniform3fv(ambientLocation, 1, colorArrayA); glUniform3fv(diffuseLocation, 1, colorArrayD); glUniform3fv(specularLocation, 1, colorArrayS); // render all meshes glBindVertexArray(vaoID[i]); // bind our VAO glDrawElements(GL_TRIANGLES, scene->mMeshes[i]->mNumFaces*3, GL_UNSIGNED_INT, 0); glBindVertexArray(0); // unbind our VAO delete [] normalArray; delete [] colorArrayA; delete [] colorArrayD; delete [] colorArrayS; } shader->unbind(); app->display(); return; } void assimpRenderer::handleEvents() { sf::Event event; while (app->pollEvent(event)) { if (event.type == sf::Event::Closed) { app->close(); } if ((event.type == sf::Event::KeyPressed) && (event.key.code == sf::Keyboard::Escape)) { app->close(); } if (event.type == sf::Event::Resized) { glViewport(0, 0, event.size.width, event.size.height); } } return; } void assimpRenderer::mainLoop(float modelScale) { while (app->isOpen()) { renderScene(modelScale); handleEvents(); } } bool assimpRenderer::assImport(const std::string& pFile) { // read the file with some example postprocessing scene = importer.ReadFile(pFile, aiProcess_CalcTangentSpace | aiProcess_Triangulate | aiProcess_JoinIdenticalVertices | aiProcess_SortByPType); // if the import failed, report it if (!scene) { std::cerr << "Error: " << importer.GetErrorString() << std::endl; return false; } return true; } void assimpRenderer::genVAOs() { int vboIndex = 0; for (unsigned int i = 0; i < scene->mNumMeshes; i++, vboIndex+=2) { mesh = scene->mMeshes[i]; indexArray = new unsigned int[mesh->mNumFaces * sizeof(unsigned int) * 3]; // convert assimp faces format to array faceIndex = 0; for (unsigned int t = 0; t < mesh->mNumFaces; ++t) { const struct aiFace* face = &mesh->mFaces[t]; std::memcpy(&indexArray[faceIndex], face->mIndices, sizeof(float) * 3); faceIndex += 3; } // generate VAO glGenVertexArrays(1, &vaoID[i]); glBindVertexArray(vaoID[i]); // generate IBO for faces glGenBuffers(1, &iboID[i]); glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, iboID[i]); glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(GLuint) * mesh->mNumFaces * 3, indexArray, GL_STATIC_DRAW); // generate VBO for vertices if (mesh->HasPositions()) { glGenBuffers(1, &vboID[vboIndex]); glBindBuffer(GL_ARRAY_BUFFER, vboID[vboIndex]); glBufferData(GL_ARRAY_BUFFER, mesh->mNumVertices * sizeof(GLfloat) * 3, mesh->mVertices, GL_STATIC_DRAW); glEnableVertexAttribArray((GLuint)0); glVertexAttribPointer((GLuint)0, 3, GL_FLOAT, GL_FALSE, 0, 0); } // generate VBO for normals if (mesh->HasNormals()) { normalArray = new float[scene->mMeshes[i]->mNumVertices * 3]; unsigned int normalIndex = 0; for (unsigned int j = 0; j < scene->mMeshes[i]->mNumVertices * 3; j+=3, normalIndex++) { normalArray[j] = scene->mMeshes[i]->mNormals[normalIndex].x; // x normalArray[j+1] = scene->mMeshes[i]->mNormals[normalIndex].y; // y normalArray[j+2] = scene->mMeshes[i]->mNormals[normalIndex].z; // z } normalIndex = 0; glGenBuffers(1, &vboID[vboIndex+1]); glBindBuffer(GL_ARRAY_BUFFER, vboID[vboIndex+1]); glBufferData(GL_ARRAY_BUFFER, mesh->mNumVertices * sizeof(GLfloat) * 3, normalArray, GL_STATIC_DRAW); glEnableVertexAttribArray((GLuint)1); glVertexAttribPointer((GLuint)1, 3, GL_FLOAT, GL_FALSE, 0, 0); delete [] normalArray; } // tex coord stuff goes here // unbind buffers glBindVertexArray(0); glBindBuffer(GL_ARRAY_BUFFER, 0); glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0); delete [] indexArray; } vboIndex = 0; return; } } file: shader.vert #version 150 core in vec3 in_Position; in vec3 in_Normal; uniform mat4 projectionMatrix; uniform mat4 viewMatrix; uniform mat4 modelMatrix; uniform vec3 lightPosition; uniform mat3 normalMatrix; smooth out vec3 vVaryingNormal; smooth out vec3 vVaryingLightDir; void main() { // derive MVP and MV matrices mat4 modelViewProjectionMatrix = projectionMatrix * viewMatrix * modelMatrix; mat4 modelViewMatrix = viewMatrix * modelMatrix; // get surface normal in eye coordinates vVaryingNormal = normalMatrix * in_Normal; // get vertex position in eye coordinates vec4 vPosition4 = modelViewMatrix * vec4(in_Position, 1.0); vec3 vPosition3 = vPosition4.xyz / vPosition4.w; // get vector to light source vVaryingLightDir = normalize(lightPosition - vPosition3); // Set the position of the current vertex gl_Position = modelViewProjectionMatrix * vec4(in_Position, 1.0); } file: shader.frag #version 150 core out vec4 out_Color; uniform vec3 ambientColor; uniform vec3 diffuseColor; uniform vec3 specularColor; smooth in vec3 vVaryingNormal; smooth in vec3 vVaryingLightDir; void main() { // dot product gives us diffuse intensity float diff = max(0.0, dot(normalize(vVaryingNormal), normalize(vVaryingLightDir))); // multiply intensity by diffuse color, force alpha to 1.0 out_Color = vec4(diff * diffuseColor, 1.0); // add in ambient light out_Color += vec4(ambientColor, 1.0); // specular light vec3 vReflection = normalize(reflect(-normalize(vVaryingLightDir), normalize(vVaryingNormal))); float spec = max(0.0, dot(normalize(vVaryingNormal), vReflection)); if (diff != 0) { float fSpec = pow(spec, 128.0); // Set the output color of our current pixel out_Color.rgb += vec3(fSpec, fSpec, fSpec); } } I know it's a lot to look through, but I'm putting most of the code up so as not to assume where the problem is. Thanks in advance to anyone who has some time to help me pinpoint the problem(s)! I've been trying to sort it out for two days now and I'm not getting anywhere on my own.

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  • DirectCompute

    In my previous blog post I introduced the concept of GPGPU ending with:On Windows, there is already a cross-GPU-vendor way of programming GPUs and that is the Direct X API. Specifically, on Windows Vista and Windows 7, the DirectX 11 API offers a dedicated subset of the API for GPGPU programming: DirectCompute. You use this API on the CPU side, to set up and execute the kernels on the GPU. The kernels are written in a language called HLSL (High Level Shader Language). You can use DirectCompute with HLSL to write a "compute shader", which is the term DirectX uses for what I've been referring to in this post as "kernel".In this post I want to share some links to get you started with DirectCompute and HLSL.1. Watch the recording of the PDC 09 session: DirectX11 DirectCompute.2. If session recordings is your thing there are two more on DirectCompute from nvidia's GTC09 conference 1015 (pdf, mp4) and 1411 (mp4 plus the presenter's written version of the session).3. Over at gamedev there is an old Compute Shader tutorial. At the same site, there is a 3-part blog post on Compute Shader: Introduction, Resources and Addressing.4. From PDC, you can also download the DirectCompute Hands On Lab.5. When you are ready to get your hands even dirtier, download the latest Windows DirectX SDK (at the time of writing the latest is dated Feb 2010).6. Within the SDK you'll find a Compute Shader Overview and samples such as: Basic, Sort, OIT, NBodyGravity, HDR Tone Mapping.7. Talking of DX11/DirectCompute samples, there are also a couple of good ones on this URL.8. The documentation of the various APIs is available online. Here are just some good (but far from complete) taster entry points into that: numthreads, SV_DispatchThreadID, SV_GroupThreadID, SV_GroupID, SV_GroupIndex, D3D11CreateDevice, D3DX11CompileFromFile, CreateComputeShader, Dispatch, D3D11_BIND_FLAG, GSSetShader. Comments about this post welcome at the original blog.

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  • gl_PointCoord always zero

    - by Jonathan
    I am trying to draw point sprites in OpenGL with a shader but gl_PointCoord is always zero. Here is my code Setup: //Shader creation..(includes glBindAttribLocation(program, ATTRIB_P, "p");) glEnableVertexAttribArray(ATTRIB_P); In the rendering loop: glUseProgram(shader_particles); float vertices[]={0.0f,0.0f,0.0f}; glEnable(GL_TEXTURE_2D); glEnable(GL_POINT_SPRITE); glEnable(GL_VERTEX_PROGRAM_POINT_SIZE); //glTexEnvi(GL_POINT_SPRITE, GL_COORD_REPLACE, GL_TRUE);(tried with this on/off, doesn't work) glVertexAttribPointer(ATTRIB_P, 3, GL_FLOAT, GL_FALSE, 0, vertices); glDrawArrays(GL_POINTS, 0, 1); Vertex Shader: attribute highp vec4 p; void main() { gl_PointSize = 40.0f; gl_Position = p; } Fragment Shader: void main() { gl_FragColor = vec4(gl_PointCoord.st, 0, 1);//if the coords range from 0-1, this should draw a square with black,red,green,yellow corners } But this only draws a black square with a size of 40. What am I doing wrong? Edit: Point sprites work when i use the fixed function, but I need to use shaders because in the end the code will be for opengl es 2.0 glUseProgram(0); glEnable(GL_TEXTURE_2D); glEnable(GL_POINT_SPRITE); glTexEnvi(GL_POINT_SPRITE, GL_COORD_REPLACE, GL_TRUE); glPointSize(40); glBegin(GL_POINTS); glVertex3f(0.0f,0.0f,0.0f); glEnd(); Is anyone able to get point sprites working with shader? If so, please share some code.

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  • Problem loading shaders with slimdx

    - by Levi
    I'm attempting to load an FX file in slimdx, I've got this exact FX file loading and compiling fine with XNA 4.0 but I'm getting errors with slimdx, here's my code to load it. using SlimDX.Direct3D11; using SlimDX.D3DCompiler; public static Effect LoadFXShader(string path) { Effect shader; using (var bytecode = ShaderBytecode.CompileFromFile(path, null, "fx_2_0", ShaderFlags.None, EffectFlags.None)) shader = new Effect(Devices.GPU.GraphicsDevice, bytecode); return shader; } Here's the shader: #define TEXTURE_TILE_SIZE 16 struct VertexToPixel { float4 Position : POSITION; float2 TextureCoords: TEXCOORD1; }; struct PixelToFrame { float4 Color : COLOR0; }; //------- Constants -------- float4x4 xView; float4x4 xProjection; float4x4 xWorld; float4x4 preViewProjection; //float random; //------- Texture Samplers -------- Texture TextureAtlas; sampler TextureSampler = sampler_state { texture = <TextureAtlas>; magfilter = Point; minfilter = point; mipfilter=linear; AddressU = mirror; AddressV = mirror;}; //------- Technique: Textured -------- VertexToPixel TexturedVS( byte4 inPos : POSITION, float2 inTexCoords: TEXCOORD0) { inPos.w = 1; VertexToPixel Output = (VertexToPixel)0; float4x4 preViewProjection = mul (xView, xProjection); float4x4 preWorldViewProjection = mul (xWorld, preViewProjection); Output.Position = mul(inPos, preWorldViewProjection); Output.TextureCoords = inTexCoords / TEXTURE_TILE_SIZE; return Output; } PixelToFrame TexturedPS(VertexToPixel PSIn) { PixelToFrame Output = (PixelToFrame)0; Output.Color = tex2D(TextureSampler, PSIn.TextureCoords); if(Output.Color.a != 1) clip(-1); return Output; } technique Textured { pass Pass0 { VertexShader = compile vs_2_0 TexturedVS(); PixelShader = compile ps_2_0 TexturedPS(); } } Now this exact shader works fine in XNA, but in slimdx I get the error ChunkDefault.fx(28,27): error X3000: unrecognized identifier 'byte4'

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  • Vertex buffer acting strange? [on hold]

    - by Ryan Capote
    I'm having a strange problem, and I don't know what could be causing it. My current code is identical to how I've done this before. I'm trying to render a rectangle using VBO and orthographic projection.   My results:     What I expect: 3x3 rectangle in the top left corner   #include <stdio.h> #include <GL\glew.h> #include <GLFW\glfw3.h> #include "lodepng.h"   static const int FALSE = 0; static const int TRUE = 1;   static const char* VERT_SHADER =     "#version 330\n"       "layout(location=0) in vec4 VertexPosition; "     "layout(location=1) in vec2 UV;"     "uniform mat4 uProjectionMatrix;"     /*"out vec2 TexCoords;"*/       "void main(void) {"     "    gl_Position = uProjectionMatrix*VertexPosition;"     /*"    TexCoords = UV;"*/     "}";   static const char* FRAG_SHADER =     "#version 330\n"       /*"uniform sampler2D uDiffuseTexture;"     "uniform vec4 uColor;"     "in vec2 TexCoords;"*/     "out vec4 FragColor;"       "void main(void) {"    /* "    vec4 texel = texture2D(uDiffuseTexture, TexCoords);"     "    if(texel.a <= 0) {"     "         discard;"     "    }"     "    FragColor = texel;"*/     "    FragColor = vec4(1.f);"     "}";   static int g_running; static GLFWwindow *gl_window; static float gl_projectionMatrix[16];   /*     Structures */ typedef struct _Vertex {     float x, y, z, w;     float u, v; } Vertex;   typedef struct _Position {     float x, y; } Position;   typedef struct _Bitmap {     unsigned char *pixels;     unsigned int width, height; } Bitmap;   typedef struct _Texture {     GLuint id;     unsigned int width, height; } Texture;   typedef struct _VertexBuffer {     GLuint bufferObj, vertexArray; } VertexBuffer;   typedef struct _ShaderProgram {     GLuint vertexShader, fragmentShader, program; } ShaderProgram;   /*   http://en.wikipedia.org/wiki/Orthographic_projection */ void createOrthoProjection(float *projection, float width, float height, float far, float near)  {       const float left = 0;     const float right = width;     const float top = 0;     const float bottom = height;          projection[0] = 2.f / (right - left);     projection[1] = 0.f;     projection[2] = 0.f;     projection[3] = -(right+left) / (right-left);     projection[4] = 0.f;     projection[5] = 2.f / (top - bottom);     projection[6] = 0.f;     projection[7] = -(top + bottom) / (top - bottom);     projection[8] = 0.f;     projection[9] = 0.f;     projection[10] = -2.f / (far-near);     projection[11] = (far+near)/(far-near);     projection[12] = 0.f;     projection[13] = 0.f;     projection[14] = 0.f;     projection[15] = 1.f; }   /*     Textures */ void loadBitmap(const char *filename, Bitmap *bitmap, int *success) {     int error = lodepng_decode32_file(&bitmap->pixels, &bitmap->width, &bitmap->height, filename);       if (error != 0) {         printf("Failed to load bitmap. ");         printf(lodepng_error_text(error));         success = FALSE;         return;     } }   void destroyBitmap(Bitmap *bitmap) {     free(bitmap->pixels); }   void createTexture(Texture *texture, const Bitmap *bitmap) {     texture->id = 0;     glGenTextures(1, &texture->id);     glBindTexture(GL_TEXTURE_2D, texture);       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);       glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bitmap->width, bitmap->height, 0,              GL_RGBA, GL_UNSIGNED_BYTE, bitmap->pixels);       glBindTexture(GL_TEXTURE_2D, 0); }   void destroyTexture(Texture *texture) {     glDeleteTextures(1, &texture->id);     texture->id = 0; }   /*     Vertex Buffer */ void createVertexBuffer(VertexBuffer *vertexBuffer, Vertex *vertices) {     glGenBuffers(1, &vertexBuffer->bufferObj);     glGenVertexArrays(1, &vertexBuffer->vertexArray);     glBindVertexArray(vertexBuffer->vertexArray);       glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer->bufferObj);     glBufferData(GL_ARRAY_BUFFER, sizeof(Vertex) * 6, (const GLvoid*)vertices, GL_STATIC_DRAW);       const unsigned int uvOffset = sizeof(float) * 4;       glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, sizeof(Vertex), 0);     glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex), (GLvoid*)uvOffset);       glEnableVertexAttribArray(0);     glEnableVertexAttribArray(1);       glBindBuffer(GL_ARRAY_BUFFER, 0);     glBindVertexArray(0); }   void destroyVertexBuffer(VertexBuffer *vertexBuffer) {     glDeleteBuffers(1, &vertexBuffer->bufferObj);     glDeleteVertexArrays(1, &vertexBuffer->vertexArray); }   void bindVertexBuffer(VertexBuffer *vertexBuffer) {     glBindVertexArray(vertexBuffer->vertexArray);     glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer->bufferObj); }   void drawVertexBufferMode(GLenum mode) {     glDrawArrays(mode, 0, 6); }   void drawVertexBuffer() {     drawVertexBufferMode(GL_TRIANGLES); }   void unbindVertexBuffer() {     glBindVertexArray(0);     glBindBuffer(GL_ARRAY_BUFFER, 0); }   /*     Shaders */ void compileShader(ShaderProgram *shaderProgram, const char *vertexSrc, const char *fragSrc) {     GLenum err;     shaderProgram->vertexShader = glCreateShader(GL_VERTEX_SHADER);     shaderProgram->fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);       if (shaderProgram->vertexShader == 0) {         printf("Failed to create vertex shader.");         return;     }       if (shaderProgram->fragmentShader == 0) {         printf("Failed to create fragment shader.");         return;     }       glShaderSource(shaderProgram->vertexShader, 1, &vertexSrc, NULL);     glCompileShader(shaderProgram->vertexShader);     glGetShaderiv(shaderProgram->vertexShader, GL_COMPILE_STATUS, &err);       if (err != GL_TRUE) {         printf("Failed to compile vertex shader.");         return;     }       glShaderSource(shaderProgram->fragmentShader, 1, &fragSrc, NULL);     glCompileShader(shaderProgram->fragmentShader);     glGetShaderiv(shaderProgram->fragmentShader, GL_COMPILE_STATUS, &err);       if (err != GL_TRUE) {         printf("Failed to compile fragment shader.");         return;     }       shaderProgram->program = glCreateProgram();     glAttachShader(shaderProgram->program, shaderProgram->vertexShader);     glAttachShader(shaderProgram->program, shaderProgram->fragmentShader);     glLinkProgram(shaderProgram->program);          glGetProgramiv(shaderProgram->program, GL_LINK_STATUS, &err);       if (err != GL_TRUE) {         printf("Failed to link shader.");         return;     } }   void destroyShader(ShaderProgram *shaderProgram) {     glDetachShader(shaderProgram->program, shaderProgram->vertexShader);     glDetachShader(shaderProgram->program, shaderProgram->fragmentShader);       glDeleteShader(shaderProgram->vertexShader);     glDeleteShader(shaderProgram->fragmentShader);       glDeleteProgram(shaderProgram->program); }   GLuint getUniformLocation(const char *name, ShaderProgram *program) {     GLuint result = 0;     result = glGetUniformLocation(program->program, name);       return result; }   void setUniformMatrix(float *matrix, const char *name, ShaderProgram *program) {     GLuint loc = getUniformLocation(name, program);       if (loc == -1) {         printf("Failed to get uniform location in setUniformMatrix.\n");         return;     }       glUniformMatrix4fv(loc, 1, GL_FALSE, matrix); }   /*     General functions */ static int isRunning() {     return g_running && !glfwWindowShouldClose(gl_window); }   static void initializeGLFW(GLFWwindow **window, int width, int height, int *success) {     if (!glfwInit()) {         printf("Failed it inialize GLFW.");         *success = FALSE;        return;     }          glfwWindowHint(GLFW_RESIZABLE, 0);     *window = glfwCreateWindow(width, height, "Alignments", NULL, NULL);          if (!*window) {         printf("Failed to create window.");         glfwTerminate();         *success = FALSE;         return;     }          glfwMakeContextCurrent(*window);       GLenum glewErr = glewInit();     if (glewErr != GLEW_OK) {         printf("Failed to initialize GLEW.");         printf(glewGetErrorString(glewErr));         *success = FALSE;         return;     }       glClearColor(0.f, 0.f, 0.f, 1.f);     glViewport(0, 0, width, height);     *success = TRUE; }   int main(int argc, char **argv) {          int err = FALSE;     initializeGLFW(&gl_window, 480, 320, &err);     glDisable(GL_DEPTH_TEST);     if (err == FALSE) {         return 1;     }          createOrthoProjection(gl_projectionMatrix, 480.f, 320.f, 0.f, 1.f);          g_running = TRUE;          ShaderProgram shader;     compileShader(&shader, VERT_SHADER, FRAG_SHADER);     glUseProgram(shader.program);     setUniformMatrix(&gl_projectionMatrix, "uProjectionMatrix", &shader);       Vertex rectangle[6];     VertexBuffer vbo;     rectangle[0] = (Vertex){0.f, 0.f, 0.f, 1.f, 0.f, 0.f}; // Top left     rectangle[1] = (Vertex){3.f, 0.f, 0.f, 1.f, 1.f, 0.f}; // Top right     rectangle[2] = (Vertex){0.f, 3.f, 0.f, 1.f, 0.f, 1.f}; // Bottom left     rectangle[3] = (Vertex){3.f, 0.f, 0.f, 1.f, 1.f, 0.f}; // Top left     rectangle[4] = (Vertex){0.f, 3.f, 0.f, 1.f, 0.f, 1.f}; // Bottom left     rectangle[5] = (Vertex){3.f, 3.f, 0.f, 1.f, 1.f, 1.f}; // Bottom right       createVertexBuffer(&vbo, &rectangle);            bindVertexBuffer(&vbo);          while (isRunning()) {         glClear(GL_COLOR_BUFFER_BIT);         glfwPollEvents();                    drawVertexBuffer();                    glfwSwapBuffers(gl_window);     }          unbindVertexBuffer(&vbo);       glUseProgram(0);     destroyShader(&shader);     destroyVertexBuffer(&vbo);     glfwTerminate();     return 0; }

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  • OpenGL Tessellation makes point

    - by urza57
    A little problem with my tessellation shader. I try to implement a simple tessellation shader but it only makes points. Here's my vertex shader : out vec4 ecPosition; out vec3 ecNormal; void main( void ) { vec4 position = gl_Vertex; gl_Position = gl_ModelViewProjectionMatrix * position; ecPosition = gl_ModelViewMatrix * position; ecNormal = normalize(gl_NormalMatrix * gl_Normal); } My tessellation control shader : layout(vertices = 3) out; out vec4 ecPosition3[]; in vec3 ecNormal[]; in vec4 ecPosition[]; out vec3 myNormal[]; void main() { gl_out[gl_InvocationID].gl_Position = gl_in[gl_InvocationID].gl_Position; myNormal[gl_InvocationID] = ecNormal[gl_InvocationID]; ecPosition3[gl_InvocationID] = ecPosition[gl_InvocationID]; gl_TessLevelOuter[0] = float(4.0); gl_TessLevelOuter[1] = float(4.0); gl_TessLevelOuter[2] = float(4.0); gl_TessLevelInner[0] = float(4.0); } And my Tessellation Evaluation shader: layout(triangles, equal_spacing, ccw) in; in vec3 myNormal[]; in vec4 ecPosition3[]; out vec3 ecNormal; out vec4 ecPosition; void main() { float u = gl_TessCoord.x; float v = gl_TessCoord.y; float w = gl_TessCoord.z; vec3 position = vec4(gl_in[0].gl_Position.xyz * u + gl_in[1].gl_Position.xyz * v + gl_in[2].gl_Position.xyz * w ); vec3 position2 = vec4(ecPosition3[0].xyz * u + ecPosition3[1].xyz * v + ecPosition3[2].xyz * w ); vec3 normal = myNormal[0] * u + myNormal[1] * v + myNormal[2] * w ); ecNormal = normal; gl_Position = vec4(position, 1.0); ecPosition = vec4(position2, 1.0); } Thank you !

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