Coloring triangles with texture

opengl-test-two/main.cpp

@@ -44,8 +44,8 @@ GLuint LoadTexture(char *filename,int *textw,int *texth) {
         // this reads from the sdl surface and puts it into an opengl texture
         glTexImage2D(GL_TEXTURE_2D, 0, mode, surface->w, surface->h, 0, mode, GL_UNSIGNED_BYTE, surface->pixels);
         // these affect how this texture is drawn later on...glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+        glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_CLAMP_TO_EDGE);
+        glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_CLAMP_TO_EDGE);
         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
         // clean up
@@ -223,13 +223,13 @@ int main(int argc, char* args[]) {
        -1.0f,  1.0f, 0.0f,  // (top    - left )
     };
     // One color for each vertex. They were generated randomly.
-    static const GLfloat g_color_buffer_data[] = {
-        0.583f,  0.771f,  0.014f,
-        0.609f,  0.115f,  0.436f,
-        0.327f,  0.483f,  0.844f,
-        0.822f,  0.569f,  0.201f,
-        0.435f,  0.602f,  0.223f,
-        0.310f,  0.747f,  0.185f,
+    static const GLfloat g_uv_buffer_data[] = {
+        0.0f, 1.0f-0.0f,         // (bottom - left )  TRIANGLE 1
+        1.0f, 1.0f-0.0f,         // (bottom - right)
+        0.0f, 1.0f-1.0f,         // (top    - left )
+        1.0f, 1.0f-1.0f,         // (top    - right)  TRIANGLE 2
+        1.0f, 1.0f-0.0f,         // (bottom - right)
+        0.0f, 1.0f-1.0f,         // (top    - left )
     };
 
 
@@ -243,7 +243,7 @@ int main(int argc, char* args[]) {
     GLuint colorbuffer;
     glGenBuffers(1, &colorbuffer);
     glBindBuffer(GL_ARRAY_BUFFER, colorbuffer);
-    glBufferData(GL_ARRAY_BUFFER, sizeof(g_color_buffer_data), g_color_buffer_data, GL_STATIC_DRAW);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(g_uv_buffer_data), g_uv_buffer_data, GL_STATIC_DRAW);
 
 
 
@@ -251,12 +251,12 @@ int main(int argc, char* args[]) {
 
 
 
-    tex_jpe=LoadTexture("../img/tests/test.jpeg",&textw,&texth);
+    tex_jpe=LoadTexture("../img/tests/test.bmp",&textw,&texth);
 
     GLuint programID = LoadShaders("trimap.vertexshader", "trimap.fragmentshader");
     printf("%d", programID);
-    //GLint textureLocation = glGetUniformLocationARB(programID, "myTextureSampler");
-    //glUniform1iARB(textureLocation, tex_jpe);
+    GLint textureLocation = glGetUniformLocationARB(programID, "myTextureSampler");
+    glUniform1i(textureLocation, tex_jpe);
 
 
 
@@ -287,7 +287,7 @@ int main(int argc, char* args[]) {
         glBindBuffer(GL_ARRAY_BUFFER, colorbuffer);
         glVertexAttribPointer(
             1,                                // attribute. No particular reason for 1, but must match the layout in the shader.
-            3,                                // size
+            2,                                // size
             GL_FLOAT,                         // type
             GL_FALSE,                         // normalized?
             0,                                // stride

opengl-test-two/opengl-test-two.depend

@@ -2,7 +2,7 @@
 1385320478 source:d:\owncloud\documents\programmierung\cpp\opengl-test-two\main.cpp
 	<iostream>
 
-1473093222 source:d:\owncloud\documents\programmierung\cpp\imanox-chroma-matting\opengl-test-two\main.cpp
+1473097371 source:d:\owncloud\documents\programmierung\cpp\imanox-chroma-matting\opengl-test-two\main.cpp
 	<GL/glew.h>
 	<GLFW/glfw3.h>
 	<SDL2/SDL.h>

opengl-test-two/trimap.fragmentshader

@@ -1,8 +1,17 @@
 #version 330 core
 
-in vec3 fragmentColor;
+// Interpolated values from the vertex shaders
+in vec2 UV;
+
+// Ouput data
 out vec3 color;
 
+// Values that stay constant for the whole mesh.
+uniform sampler2D myTextureSampler;
+
 void main(){
-    color = fragmentColor;
+
+    // Output color = color of the texture at the specified UV
+    color = texture( myTextureSampler, UV ).rgb;
 }
+

opengl-test-two/trimap.vertexshader

@@ -1,11 +1,17 @@
 #version 330 core
 
+// Input vertex data, different for all executions of this shader.
 layout(location = 0) in vec3 vertexPosition_modelspace;
-layout(location = 1) in vec3 vertexColor;
-out vec3 fragmentColor;
+layout(location = 1) in vec2 vertexUV;
+
+// Output data ; will be interpolated for each fragment.
+out vec2 UV;
 
 void main(){
-    gl_Position.xyz = vertexPosition_modelspace;
-    gl_Position.w = 1.0;
-    fragmentColor = vertexColor;
+    // Output position of the vertex, in clip space : MVP * position
+    gl_Position = vec4(vertexPosition_modelspace,1);
+
+    // UV of the vertex. No special space for this one.
+    UV = vertexUV;
 }
+