transparent-cube

commit 4268464c78aa655b36928a7e5cb03b426bd103e5
parent daa817605484e5a9abe9d242872b69ea3ebcac08
Author: amin <dev@aminmesbah.com>
Date:   Fri, 21 Jun 2019 02:23:55 +0000

Produce the first flicker of life

FossilOrigin-Name: 7a8f9a1155a334df96af6a286a1a15b4e01090095931b1882e924e6ecf4b38e1
Diffstat:
M
src/game.c
 | 
6
++----
M
src/game.h
 | 
14
+++++++-------
M
src/glmth.h
 | 
34
+++++++++++++++++++++++++++++++++-
M
src/platform_wasm.c
 | 
5
++++-

4 files changed, 46 insertions(+), 13 deletions(-)
diff --git a/src/game.c b/src/game.c
@@ -52,7 +52,6 @@ void game_init(struct GameState *game_state, u32 screen_width, u32 screen_height
         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, cube_ebo);
         glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(elements), elements, GL_STATIC_DRAW);
 
-        glBindVertexArray(0);
 
         game_state->cube_vao = cube_vao;
         game_state->cube_vbo = cube_vbo;
@@ -91,7 +90,8 @@ void game_update_and_render(struct GameState *game_state, float dt, u32 screen_w
     m4 view = glmth_m4_init_id();
     m4 projection = glmth_m4_init_id();
     view = glmth_translate(view, glmth_v3_init(0.0f, 0.0f, -3.0f));
-    projection = glmth_projection_perspective_fov(glmth_rad(45.0f), (float)screen_width / (float)screen_height, 0.1f, 100.0f);
+    //projection = glmth_projection_perspective_fov(glmth_rad(45.0f), (float)screen_width / (float)screen_height, 0.1f, 100.0f);
+    projection = glmth_projection_ortho(0.0f, screen_width, 0.0f, screen_height, -10.0f, 10.0f);
 
     // render cube
     {
@@ -118,9 +118,7 @@ void game_update_and_render(struct GameState *game_state, float dt, u32 screen_w
         shader_setm4(&game_state->cube_shader, "model", &model);
         shader_setf(&game_state->cube_shader, "alpha", alpha);
 
-        glBindVertexArray(game_state->cube_vao);
         glDrawElements(GL_TRIANGLES, 36, GL_UNSIGNED_INT, 0);
-        glBindVertexArray(0);
 
         glEnable(GL_DEPTH_TEST);
         glDisable(GL_BLEND);
diff --git a/src/game.h b/src/game.h
@@ -9,29 +9,29 @@
 // TODO: fix this
 #define assert(x) (void)0
 
-inline float sinf(float a)
+inline float sinf(float x)
 {
-    return a;
+    return x;
 }
 
-inline float cosf(float a)
+inline float cosf(float x)
 {
-    return a;
+    return x;
 }
 
 inline float powf(float x, float p)
 {
-    return x;
+    return x * x;
 }
 
 inline float sqrtf(float a)
 {
-    return a;
+    return a * 0.5f;
 }
 
 inline float tanf(float a)
 {
-    return a;
+    return 0.4142135623730950488f;
 }
 
 typedef _Bool bool;
diff --git a/src/glmth.h b/src/glmth.h
@@ -156,7 +156,7 @@ static inline f32 glmth_rad(f32 deg)
 
 static inline m4 glmth_rotate(m4 m, f32 rad, v3 axis)
 {
-    axis = glmth_v3_normalize(axis);
+    //axis = glmth_v3_normalize(axis);
 
     f32 c = cosf(rad);
     f32 s = sinf(rad);
@@ -187,6 +187,38 @@ static inline m4 glmth_translate(m4 m, v3 v)
     return glmth_m4m4_m(m, r);
 }
 
+static inline m4 glmth_projection_ortho(f32 left, f32 right, f32 bottom, f32 top, f32 near, f32 far)
+{
+    // TODO: This assert fails when you minimise the window in Windows.
+    assert(left != right);
+    assert(bottom != top);
+    assert(near != far);
+
+    m4 r = glmth_m4_init_id();
+
+    r.E[0][0] = 2.0f / (right - left);
+    r.E[0][1] = 0.0f;
+    r.E[0][2] = 0.0f;
+    r.E[0][3] = -(right + left) / (right - left);
+
+    r.E[1][0] = 0.0f;
+    r.E[1][1] = 2.0f / (top - bottom);
+    r.E[1][2] = 0.0f;
+    r.E[1][3] = -(top + bottom) / (top - bottom);
+
+    r.E[2][0] = 0.0f;
+    r.E[2][1] = 0.0f;
+    r.E[2][2] = -2.0f / (far - near);
+    r.E[2][3] = -(far + near) / (far - near);
+
+    r.E[3][0] = 0.0f;
+    r.E[3][1] = 0.0f;
+    r.E[3][2] = 0.0f;
+    r.E[3][3] = 1.0f;
+
+    return r;
+}
+
 static inline m4 glmth_projection_perspective(f32 left, f32 right, f32 bottom, f32 top, f32 near, f32 far)
 {
     assert(left != right);
diff --git a/src/platform_wasm.c b/src/platform_wasm.c
@@ -12,6 +12,8 @@ i32 g_width = PLATFORM_SCR_WIDTH;
 i32 g_height = PLATFORM_SCR_HEIGHT;
 char g_mem_buffer[1000] = {0};
 i32 g_mem_buffer_i = 0;
+u32 time = 0;
+
 
 export bool init(void)
 {
@@ -24,7 +26,8 @@ export bool init(void)
 
 export void render(void)
 {
-    game_update_and_render(&g_game_state, 16, g_width, g_height);
+    time += 16;
+    game_update_and_render(&g_game_state, time, g_width, g_height);
 }
 
 export void window_resize(int w, int h)