diff options
| -rw-r--r-- | gl.c | 1 | ||||
| -rw-r--r-- | main.c | 20 |
2 files changed, 12 insertions, 9 deletions
@@ -125,4 +125,3 @@ static GLint gl_uniform_loc(GLuint program, char const *uniform) { return loc; } - @@ -283,28 +283,31 @@ int main(int argc, char **argv) { char const *vshader_code = "#version 110\n\ attribute vec2 v_pos;\n\ +attribute vec4 v_color;\n\ +varying vec4 color;\n\ uniform vec2 window_size;\n\ void main() {\n\ float x = v_pos.x / window_size.x * 2.0 - 1.0;\n\ float y = 1.0 - v_pos.y / window_size.y * 2.0;\n\ gl_Position = vec4(x, y, 0.0, 1.0);\n\ + color = v_color;\n\ }\n\ "; char const *fshader_code = "#version 110\n\ -uniform vec4 color;\n\ +varying vec4 color;\n\ void main() {\n\ gl_FragColor = color;\n\ }\n\ "; - float vertices[][2] = { - {0, 0}, - {50, 0}, - {0, 50}, + float vertices[][6] = { + {0, 0, 1, 0, 0, 1}, + {50, 0, 0, 1, 0, 1}, + {0, 50, 0, 0, 1, 1}, }; GLuint program = gl_compile_and_link_shaders(vshader_code, fshader_code); GLuint v_pos = gl_attrib_loc(program, "v_pos"); + GLuint v_color = gl_attrib_loc(program, "v_color"); GLint u_window_size = gl_uniform_loc(program, "window_size"); - GLint u_color = gl_uniform_loc(program, "color"); GLuint vbo = 0, vao = 0; glGenBuffers(1, &vbo); @@ -313,8 +316,10 @@ void main() {\n\ glBindVertexArray(vao); glBindBuffer(GL_ARRAY_BUFFER, vbo); glBufferData(GL_ARRAY_BUFFER, sizeof vertices, vertices, GL_STATIC_DRAW); - glVertexAttribPointer(v_pos, 2, GL_FLOAT, 0, 2 * sizeof(float), (void *)0); + glVertexAttribPointer(v_pos, 2, GL_FLOAT, 0, 6 * sizeof(float), (void *)0); glEnableVertexAttribArray(v_pos); + glVertexAttribPointer(v_color, 4, GL_FLOAT, 0, 6 * sizeof(float), (void *)(2 * sizeof(float))); + glEnableVertexAttribArray(v_color); glBindVertexArray(0); while (1) { @@ -330,7 +335,6 @@ void main() {\n\ glUseProgram(program); - glUniform4f(u_color, 1, 1, 0, 1); glUniform2f(u_window_size, (float)w, (float)h); glBindVertexArray(vao); |