diff options
| -rw-r--r-- | main.c | 44 |
1 files changed, 24 insertions, 20 deletions
@@ -12,6 +12,10 @@ // custom SDL_USEREVENT code for timer #define EVENT_CODE_TIMER 0 +#define NUM_PARTICLES 1000 +#define SS(v) #v +#define S(v) SS(v) + typedef struct { const GLuint type; const char *src; @@ -42,10 +46,10 @@ static const char vs_src[] = "#version 320 es\n" "\n" - "layout (std140, binding = 0) uniform particles {\n" - " mediump vec4 positions[1000];\n" - " mediump vec4 velocities[1000];\n" - " mediump vec4 colors[1000];\n" + "layout (std140, binding = 0) buffer particles {\n" + " mediump vec4 positions[" S(NUM_PARTICLES) "];\n" + " mediump vec4 velocities[" S(NUM_PARTICLES) "];\n" + " mediump vec4 colors[" S(NUM_PARTICLES) "];\n" "};\n" "\n" "layout (location = 0) in mediump vec3 pos;\n" @@ -59,10 +63,10 @@ static const char fs_src[] = "#version 320 es\n" "\n" - "layout (std140, binding = 0) uniform particles {\n" - " mediump vec4 positions[1000];\n" - " mediump vec4 velocities[1000];\n" - " mediump vec4 colors[1000];\n" + "layout (std140, binding = 0) buffer particles {\n" + " mediump vec4 positions[" S(NUM_PARTICLES) "];\n" + " mediump vec4 velocities[" S(NUM_PARTICLES) "];\n" + " mediump vec4 colors[" S(NUM_PARTICLES) "];\n" "};\n" "\n" "out mediump vec4 color;\n" @@ -352,15 +356,15 @@ int main(int argc, char *argv[]) { glGenVertexArrays(1, &vao); glBindVertexArray(vao); - // generate uniform buffer - GLuint ubo; - glGenBuffers(1, &ubo); - glBindBuffer(GL_UNIFORM_BUFFER, ubo); - glBufferData(GL_UNIFORM_BUFFER, 1000 * 3 * 4 * sizeof(GLfloat), NULL, GL_STATIC_DRAW); - glBindBuffer(GL_UNIFORM_BUFFER, 0); + // generate shader storage buffer + GLuint ssbo; + glGenBuffers(1, &ssbo); + glBindBuffer(GL_SHADER_STORAGE_BUFFER, ssbo); + glBufferData(GL_SHADER_STORAGE_BUFFER, NUM_PARTICLES * 3 * 4 * sizeof(GLfloat), NULL, GL_STATIC_DRAW); + glBindBuffer(GL_SHADER_STORAGE_BUFFER, 0); // bind uniform buffer to slot 0 - glBindBufferBase(GL_UNIFORM_BUFFER, 2, ubo); + // glBindBufferBase(GL_UNIFORM_BUFFER, 2, ubo); // generate vertex buffer GLuint vbo; @@ -375,8 +379,8 @@ int main(int argc, char *argv[]) { glBindVertexArray(0); // link program, get uniforms - GLuint prog = link_program(2, RENDER_SHADERS); - GLint u_time = glGetUniformLocation(prog, "time"); + GLuint render_prog = link_program(2, RENDER_SHADERS); + GLint u_time = glGetUniformLocation(render_prog, "time"); // main loop while (!ctx.done) { @@ -390,13 +394,13 @@ int main(int argc, char *argv[]) { glClearColor(0, 0, 0, 1); glClear(GL_COLOR_BUFFER_BIT); - // use program, set uniform - glUseProgram(prog); + // use render program, set uniform + glUseProgram(render_prog); glUniform1f(u_time, now / 1000.0); // draw glBindVertexArray(vao); - glDrawArraysInstanced(GL_TRIANGLES, 0, 3, 1000); + glDrawArraysInstanced(GL_TRIANGLES, 0, 3, NUM_PARTICLES); glBindVertexArray(0); // swap buffer |