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About Terrimus

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  1. Terrimus

    SOLVED: Triangle Strip + GLSL = ?

    I thought attribute variables could be changed at any time? Anyway, I just found a way around setting the variable per vertex as I thought I had to do. Edit: I misunderstood your post. Now I see, I can set the attribute variables, but not get the location of the between glBegin-glEnd :)
  2. I have this test code which works: GLShader shader("shaders/test.vert", "shaders/test.frag"); ... shader.bind(); for(int j = 0; j < 100; j += 10) { shader.setAttrib1f("a", 1.0f); glBegin(GL_TRIANGLE_STRIP); for(int i = 0; i < 100; i += 10) { glVertex3f(i, 0, j); glVertex3f(i, 0, j + 10); } glEnd(); } shader.unbind(); but if I put the setAttrib-call inside the blBegin(), I get some strange results. This: glBegin(GL_TRIANGLE_STRIP); for(int i = 0; i < 100; i += 10) { shader.setAttrib1f("a", 1.0f); glVertex3f(i, 0, j); glVertex3f(i, 0, j + 10); } gives me: I've used shaders + triangle strip before without this issue, and I really don't understand what is wrong. The shaders are really basic: vert: attribute float a; void main() { vec4 v = vec4(gl_Vertex); v.y = a; gl_Position = gl_ModelViewProjectionMatrix * v; } frag: void main() { gl_FragColor = vec4(1, 1, 1, 1); } The setAttrib-function: void GLShader::setAttrib1f(const char* name, float value) { GLint location = glGetAttribLocationARB(m_prog, name); glVertexAttrib1fARB(location, value); } [Edited by - Terrimus on December 3, 2009 7:14:30 PM]
  3. Again, I think I've solved the problem. I added a '\0' to the buffer returned from my textfile-reading method. Stupid error, but now I know :)
  4. Ok, thanks for the tip :)
  5. This is from the render-function in the heightmap-class: ... if(m_shader.getID() == 0) m_shader.load("shaders/terrain.vert", "shaders/terrain.frag"); m_shader.bind(); if(m_textures[0] == 0) { m_textures[0] = TextureManager::getInstance()->createTexture("data/arrow.tga"); m_textures[1] = TextureManager::getInstance()->createTexture("data/grass.tga"); m_textures[2] = TextureManager::getInstance()->createTexture("data/mountain.tga"); m_shader.setUniform1i("arrow", 0); m_shader.setUniform1i("grass", 1); m_shader.setUniform1i("mount", 2); } glActiveTextureARB(GL_TEXTURE0_ARB); glBindTexture(GL_TEXTURE_2D, m_textures[0]); glEnable(GL_TEXTURE_2D); glActiveTextureARB(GL_TEXTURE1_ARB); glBindTexture(GL_TEXTURE_2D, m_textures[1]); glEnable(GL_TEXTURE_2D); glActiveTextureARB(GL_TEXTURE2_ARB); glBindTexture(GL_TEXTURE_2D, m_textures[2]); glEnable(GL_TEXTURE_2D); ...
  6. Well, after 3-4 hours trying to avoid cryptic errors and things not working, it seems like I've got my code to work (as expected). I am trying to write a simple shader for textureing a heightmap. But to be able to set the sampler2D-variables in my fragment shader I have to declare an empty variable first? this doesn't work: uniform sampler2D arrow, grass, mount; void main() { // vec4 color = texture2D(tex0, vec2(gl_TexCoord[0])) + texture2D(tex1, vec2(gl_TexCoord[0])) + texture2D(tex2, vec2(gl_TexCoord[0])); gl_FragColor = texture2D(mount, vec2(gl_TexCoord[0])); } but this do: uniform sampler2D x, arrow, grass, mount; void main() { // vec4 color = texture2D(tex0, vec2(gl_TexCoord[0])) + texture2D(tex1, vec2(gl_TexCoord[0])) + texture2D(tex2, vec2(gl_TexCoord[0])); gl_FragColor = texture2D(mount, vec2(gl_TexCoord[0])); } Though my code work as I want now, I really want to know why I have to declare that variable. Is it an issue with my graphic card (NVIDIA GeForce 8200M)?
  7. Terrimus

    GLSL: strange syntax error?

    Think I've solved it. I changed my shader-class to properly detach and delete the shaders/program, and now it seems to work. So if anyone else have the same problem try that :P
  8. Terrimus

    GLSL: strange syntax error?

    Hm, maybe there is a issue with my graphic card driver? Seems like glGetUniformLocation allways return -1.
  9. Terrimus

    GLSL: strange syntax error?

    *bump* new strange syntax error :S (see top)
  10. Terrimus

    GLSL: strange syntax error?

    I apparently fixed it. Just added if(!GLEW_ARB_multitexture || (glActiveTexture == NULL) || (glClientActiveTexture == NULL)) { cout << "Warning! No multitexture support!" << endl; } in my glew-initiating method, and now it works. :O
  11. Hi I am getting some strange (and random) errors when trying to use a shader. Fragment info ------------- 0(14) : error C0000: syntax error, unexpected $undefined at token "<undefined>" 0(14) : error C0501: type name expected at token "<undefined>" This is a simple shader just taking the color from the the first texture Vertex: void main() { gl_TexCoord[0] = gl_MultiTexCoord0; gl_Position = ftransform(); } Fragment: uniform sampler2D Texture0; uniform sampler2D Texture1; void main() { vec4 tex0, tex1; tex0 = texture2D(Texture0, gl_TexCoord[0].st); tex1 = texture2D(Texture1, gl_TexCoord[0].st); gl_FragColor = tex1; } I've run this code some times, and sometimes I get the error, sometimes I don't. But I can't see any syntax errors? I set the TextureX-variables like this: glUniform1i(glGetUniformLocation(programID, "Texture0"), tex0); [Edited by - Terrimus on November 26, 2009 11:20:05 AM]
  12. Ok, thanks. I've just wanted to try to use quaternions because I wanted to learn it, but guess they still are over my head. I'm sticking to matrices for now :)
  13. Hi I'm trying to create a simple camera class. I'm using 3 vectors (eye, view, up) and trying to use quaternions for rotation, but getting undesirable results (e.g. crazy results). I'm only rendering a quad at (0, 0, -10). When I try to rotate the cam it just seem to spin around the origo. But when I move the camera, suddenly it appear a different place or totaly disappear. I've checked the quaternion-class against the calculator here and it seems to work. I've got a rotation-function in the camera class which rotates the camera-view around the Y-axis: axis.x = 0; axis.y = 1; axis.z = 0; Quat tmp = createRotationQuaternion(angle, axis); Quat view(0, m_view.x, m_view.y, m_view.z); Quat res = (tmp * view) * conjugate(tmp); m_view.x = res.x; m_view.y = res.y; m_view.z = res.z; The createRotationQuaternion(float, Vec3) looks like this: Quat createRotationQuaternion(const float angle, const Vec3& axis) { float halfTheta = angle * 0.5f; float sinHalfTheta = sinf(halfTheta); float w = cosf(halfTheta); float x = sinHalfTheta * axis.x; float y = sinHalfTheta * axis.y; float z = sinHalfTheta * axis.z; return Quat(w, x, y, z); } I am using gluLookAt() to apply the camera. The whole code can be viewed here:
  14. Terrimus

    Matrix combined transformation and rotation

    Yes, I know that I have to invert the transformation (the way I have it now I just "invert" the values on keypress. E.g. when I press forward I actually move backwards. I almost have it working now, but I get some strange results. It seems to work when I start the application, but when I do some rotation/strafing I get the strange results. Again; I want to move (translate along the Z-axis according to the rotation), and strafe (translate along the X-axis according to the rotation). Any good articles/books on this subject? Found a lot about matrices/transformations, but nothing about how to actually implement it in a game engine :(
  15. Terrimus

    Matrix combined transformation and rotation

    1. column-major (since I am using OpenGL) 2. no idea ;) a vector is simple stored as three floats xyz 3. m_trans is an instance of my Matrix-class in the camera class. It holds the camera's transformation 4. currently I am not doing any inverting 5. I doubt it. I 'apply' my camera with glMultMatrix, the same way I itend to apply the transformations of the nodes in my scene graph. glPushMatrix(); glLoadMatrix(m_trans.getData()); glPopMatrix();
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