summaryrefslogtreecommitdiff
path: root/main.c
diff options
context:
space:
mode:
Diffstat (limited to 'main.c')
-rw-r--r--main.c218
1 files changed, 119 insertions, 99 deletions
diff --git a/main.c b/main.c
index cc70405..6a50d5e 100644
--- a/main.c
+++ b/main.c
@@ -7,6 +7,14 @@
static mat4 g_camera;
static bool g_wireframe;
+static const uint32_t tex_width = 1024;
+
+typedef struct {
+ vec3 pos;
+} UnlitVertex;
+typedef struct {
+ vec2 pos;
+} UpdateVertex;
typedef struct {
GLuint grains_tex1, grains_tex2;
@@ -16,6 +24,10 @@ typedef struct {
float grain_gen_radius;
float color_speed_scale;
vec4 color1, color2; // color1 = color of still grain, color2 = color of grain moving at color_speed_scale m/s
+ GLProgram grain_program, update_program;
+ GLVBO update_vbo, grain_vbo;
+ GLVAO update_vao, grain_vao;
+ uint32_t tex_height;
} Function;
typedef struct {
@@ -32,33 +44,22 @@ static void APIENTRY gl_message_callback(GLenum source, GLenum type, unsigned in
debug_print("Message from OpenGL: %s.\n", message);
}
-int main(int argc, char **argv) {
- if (!window_create("sandbox", 1280, 720, 0)) {
- return -1;
- }
- if (gl_version_major * 100 + gl_version_minor < 310) {
- window_message_box_error("Error", "Couldn't get OpenGL 3.1 context (your graphics drivers are too old).");
- return -1;
- }
-
- Player player_data = {0}, *player = &player_data;
- Function f_data = {0}, *f = &f_data;
-
- typedef struct {
- vec3 pos;
- } UnlitVertex;
- typedef struct {
- vec2 pos;
- } UpdateVertex;
+static GLuint g_grain_vshader, g_update_vshader;
- GLProgram update_program = {0}, grain_program = {0};
- const char *wind_formula = "y * y * tan(z), z * z, -x * x";
+static void function_create(Function *f, const char *wind_formula) {
+ {
+ GLuint tex[2] = {0};
+ gl.GenTextures(2, tex);
+ f->grains_tex1 = tex[0];
+ f->grains_tex2 = tex[1];
+ }
+ f->color_speed_scale = 10;
+ f->ngrains = 500000;
+ f->new_grains_per_second = 1000;
+ f->grain_gen_radius = 2;
+ f->color1 = Vec4(1.0f,0.8f,.6f,1);
+ f->color2 = Vec4(1.0f,0,0,1);
{
- const char *vshader_code =
- "attribute vec2 v_pos;\n"
- "void main() {\n"
- " gl_Position = vec4(v_pos, 0.0, 1.0);\n"
- "}\n";
static char fshader_code[65536];
strbuf_print(fshader_code,
@@ -94,33 +95,21 @@ int main(int argc, char **argv) {
wind_formula
);
- GLuint vshader = V_gl_shader_compile_code("updatev.glsl", NULL, vshader_code, GL_VERTEX_SHADER);
GLuint fshader = V_gl_shader_compile_code("updatef.glsl", NULL, fshader_code, GL_FRAGMENT_SHADER);
GLint status = 0;
GLuint prog = gl.CreateProgram();
- gl.AttachShader(prog, vshader);
+ gl.AttachShader(prog, g_update_vshader);
gl.AttachShader(prog, fshader);
gl.LinkProgram(prog);
gl.GetProgramiv(prog, GL_LINK_STATUS, &status);
- gl.DetachShader(prog, vshader);
+ gl.DetachShader(prog, g_update_vshader);
gl.DetachShader(prog, fshader);
+ gl.DeleteShader(fshader);
assert(status);
- update_program.id = prog;
+ f->update_program.id = prog;
}
- f->color_speed_scale = 10;
{
- const char *vshader_code =
- "attribute vec3 v_pos;\n"
- "uniform mat4 u_transform;\n"
- "uniform sampler2D u_offset_tex;\n"
- "varying vec3 pos;\n"
- "void main() {\n"
- " ivec2 texel_pos = ivec2(gl_InstanceID & 1023, gl_InstanceID >> 10);\n"
- " vec3 offset = texelFetch(u_offset_tex, texel_pos, 0).xyz;\n"
- " gl_Position = u_transform * vec4(v_pos + offset, 1.0);\n"
- " pos = v_pos + offset;\n"
- "}\n";
static char fshader_code[65536];
strbuf_print(fshader_code,
"uniform vec4 u_color1, u_color2;\n"
@@ -133,23 +122,21 @@ int main(int argc, char **argv) {
wind_formula,
f->color_speed_scale == 0 ? 1 : 1.0f / f->color_speed_scale
);
- GLuint vshader = V_gl_shader_compile_code("grainv.glsl", NULL, vshader_code, GL_VERTEX_SHADER);
GLuint fshader = V_gl_shader_compile_code("grainf.glsl", NULL, fshader_code, GL_FRAGMENT_SHADER);
GLint status = 0;
GLuint prog = gl.CreateProgram();
- gl.AttachShader(prog, vshader);
+ gl.AttachShader(prog, g_grain_vshader);
gl.AttachShader(prog, fshader);
gl.LinkProgram(prog);
gl.GetProgramiv(prog, GL_LINK_STATUS, &status);
- gl.DetachShader(prog, vshader);
+ gl.DetachShader(prog, g_grain_vshader);
gl.DetachShader(prog, fshader);
+ gl.DeleteShader(fshader);
assert(status);
- grain_program.id = prog;
+ f->grain_program.id = prog;
}
-
-
- GLVBO update_vbo = gl_vbo_new(UpdateVertex, "update");
- GLVAO update_vao = gl_vao_new(&update_program, "update");
+ f->update_vbo = gl_vbo_new(UpdateVertex, "update");
+ f->update_vao = gl_vao_new(&f->update_program, "update");
{
UpdateVertex vertices[] = {
{-1,-1},
@@ -159,12 +146,12 @@ int main(int argc, char **argv) {
{+1,+1},
{-1,+1}
};
- gl_vbo_set_static_data(&update_vbo, vertices, static_arr_len(vertices));
- gl_vao_add_data2f(&update_vao, update_vbo, "v_pos", UpdateVertex, pos);
+ gl_vbo_set_static_data(&f->update_vbo, vertices, static_arr_len(vertices));
+ gl_vao_add_data2f(&f->update_vao, f->update_vbo, "v_pos", UpdateVertex, pos);
}
- GLVBO grain_vbo = gl_vbo_new(UnlitVertex, "grain");
- GLVAO grain_vao = gl_vao_new(&grain_program, "grain");
+ f->grain_vbo = gl_vbo_new(UnlitVertex, "grain");
+ f->grain_vao = gl_vao_new(&f->grain_program, "grain");
{
float h = 0.005f;
float S3 = 0.57735026919f; // sqrt(1/3)
@@ -176,37 +163,22 @@ int main(int argc, char **argv) {
{0,-h*.5f,-h*S3},
{0,-h*.5f,+h*S3},
};
- gl_vbo_set_static_data(&grain_vbo, vertices, static_arr_len(vertices));
- gl_vao_add_data3f(&grain_vao, grain_vbo, "v_pos", UnlitVertex, pos);
- }
-
-
- window_set_relative_mouse(1);
-
- {
- GLuint tex[2] = {0};
- gl.GenTextures(2, tex);
- f->grains_tex1 = tex[0];
- f->grains_tex2 = tex[1];
+ gl_vbo_set_static_data(&f->grain_vbo, vertices, static_arr_len(vertices));
+ gl_vao_add_data3f(&f->grain_vao, f->grain_vbo, "v_pos", UnlitVertex, pos);
}
- f->ngrains = 1000000;
- f->new_grains_per_second = 1000;
- f->grain_gen_radius = 2;
- f->color1 = Vec4(1.0f,0.8f,.6f,1);
- f->color2 = Vec4(1.0f,0,0,1);
- const uint32_t tex_width = 1024;
uint32_t tex_chunk_size = tex_width * 4; // height must be a multiple of 4
uint32_t tex_area = ((f->ngrains + tex_chunk_size-1) / tex_chunk_size) * tex_chunk_size; // width * height of grain pos texture
if (tex_area < tex_chunk_size) tex_area = tex_chunk_size;
uint32_t tex_height = tex_area / tex_width;
+ f->tex_height = tex_height;
{
size_t ndata = (size_t)((f->ngrains + tex_chunk_size - 1) / tex_chunk_size) * tex_chunk_size;
vec3 *data = calloc(ndata, sizeof *data); // required to initialize textures to NAN
if (!data) {
window_message_box_error("Out of memory", "Not enough memory for grains. Try reducing the max number of grains.");
- return -1;
+ exit(-1);
}
for (int i = 0; i < ndata; ++i) {
data[i] = Vec3(NAN, NAN, NAN);
@@ -227,10 +199,58 @@ int main(int argc, char **argv) {
gl.TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
free(data);
+ }
+ gl.GenFramebuffers(1, &f->fbo);
+}
+int main(int argc, char **argv) {
+ if (!window_create("sandbox", 1280, 720, 0)) {
+ return -1;
+ }
+ if (gl_version_major * 100 + gl_version_minor < 310) {
+ window_message_box_error("Error", "Couldn't get OpenGL 3.1 context (your graphics drivers are too old).");
+ return -1;
}
- gl.GenFramebuffers(1, &f->fbo);
+ Player player_data = {0}, *player = &player_data;
+ Function *functions = NULL;
+
+
+ window_set_relative_mouse(1);
+
+ // global shader programs
+ {
+ const char *vshader_code =
+ "attribute vec2 v_pos;\n"
+ "void main() {\n"
+ " gl_Position = vec4(v_pos, 0.0, 1.0);\n"
+ "}\n";
+ g_update_vshader = V_gl_shader_compile_code("updatev.glsl", NULL, vshader_code, GL_VERTEX_SHADER);
+ }
+ {
+ const char *vshader_code =
+ "attribute vec3 v_pos;\n"
+ "uniform mat4 u_transform;\n"
+ "uniform sampler2D u_offset_tex;\n"
+ "varying vec3 pos;\n"
+ "void main() {\n"
+ " ivec2 texel_pos = ivec2(gl_InstanceID & 1023, gl_InstanceID >> 10);\n"
+ " vec3 offset = texelFetch(u_offset_tex, texel_pos, 0).xyz;\n"
+ " gl_Position = u_transform * vec4(v_pos + offset, 1.0);\n"
+ " pos = v_pos + offset;\n"
+ "}\n";
+ g_grain_vshader = V_gl_shader_compile_code("grainv.glsl", NULL, vshader_code, GL_VERTEX_SHADER);
+ }
+
+ {
+ Function *f = arr_addp(functions);
+ function_create(f, "y * y * tan(z), z * z, -x * x");
+ }{
+ Function *f = arr_addp(functions);
+ function_create(f, "-y * y * tan(z), -z * z, x * x");
+ }
+
+
bool fullscreen = false;
@@ -285,19 +305,19 @@ int main(int argc, char **argv) {
gl.Enable(GL_DEPTH_TEST);
- {
- gl.Viewport(0,0,(GLsizei)tex_width,(GLsizei)tex_height);
+ arr_foreachp(functions, Function, f) {
+ gl.Viewport(0,0,(GLsizei)tex_width,(GLsizei)f->tex_height);
gl.BindFramebuffer(GL_FRAMEBUFFER, f->fbo);
gl.FramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, f->grains_tex2, 0);
- gl_program_use(&update_program);
+ gl_program_use(&f->update_program);
gl.ActiveTexture(GL_TEXTURE0);
gl.BindTexture(GL_TEXTURE_2D, f->grains_tex1);
- gl_uniform1i(&update_program, "u_tex", 0);
- gl_uniform1i(&update_program, "u_new_grains_per_second", (GLint)f->new_grains_per_second);
- gl_uniform1f(&update_program, "u_dt", dt);
- gl_uniform1f(&update_program, "u_rand_seed", randf());
- gl_uniform1f(&update_program, "u_grain_gen_radius", f->grain_gen_radius);
- gl_vao_render(update_vao, NULL);
+ gl_uniform1i(&f->update_program, "u_tex", 0);
+ gl_uniform1i(&f->update_program, "u_new_grains_per_second", (GLint)f->new_grains_per_second);
+ gl_uniform1f(&f->update_program, "u_dt", dt);
+ gl_uniform1f(&f->update_program, "u_rand_seed", randf());
+ gl_uniform1f(&f->update_program, "u_grain_gen_radius", f->grain_gen_radius);
+ gl_vao_render(f->update_vao, NULL);
}
gl.BindFramebuffer(GL_FRAMEBUFFER, 0);
@@ -309,24 +329,24 @@ int main(int argc, char **argv) {
vec3 p = player->pos;
g_camera = mat4_camera(p, player->yaw, player->pitch, degree2rad(45), 1, 50);
}
- gl_program_use(&grain_program);
- gl_uniformM4(&grain_program, "u_transform", &g_camera);
- gl_uniform4f(&grain_program, "u_color1", f->color1);
- gl_uniform4f(&grain_program, "u_color2", f->color2);
- gl.BindTexture(GL_TEXTURE_2D, f->grains_tex2);
- gl.ActiveTexture(GL_TEXTURE0);
-
- gl_uniform1i(&grain_program, "u_offset_tex", 0);
-
-
- gl.BindVertexArray(grain_vao.id);
- gl.DrawArraysInstanced(GL_TRIANGLES, 0, 6, (GLsizei)f->ngrains);
-
- { // swap "front and back" grain textures
- GLuint temp = f->grains_tex1;
- f->grains_tex1 = f->grains_tex2;
- f->grains_tex2 = temp;
+ arr_foreachp(functions, Function, f) {
+ gl_program_use(&f->grain_program);
+ gl_uniformM4(&f->grain_program, "u_transform", &g_camera);
+ gl_uniform4f(&f->grain_program, "u_color1", f->color1);
+ gl_uniform4f(&f->grain_program, "u_color2", f->color2);
+ gl.BindTexture(GL_TEXTURE_2D, f->grains_tex2);
+ gl.ActiveTexture(GL_TEXTURE0);
+ gl_uniform1i(&f->grain_program, "u_offset_tex", 0);
+ gl.BindVertexArray(f->grain_vao.id);
+ gl.DrawArraysInstanced(GL_TRIANGLES, 0, 6, (GLsizei)f->ngrains);
+
+ { // swap "front and back" grain textures
+ GLuint temp = f->grains_tex1;
+ f->grains_tex1 = f->grains_tex2;
+ f->grains_tex2 = temp;
+ }
}
+
}
generated by cgit v1.2.3 (git 2.39.1) at 2025-07-01 09:05:29 +0000