Merge pull request floooh#1 from floooh/master

Bringing fresh from flooh

util/sokol_fontstash.h

@@ -1,4 +1,4 @@
-#pragma once
+#ifndef SOKOL_FONTSTASH_INCLUDED
 /*
     sokol_fontstash.h -- renderer for https://github.com/memononen/fontstash
                          on top of sokol_gl.h
@@ -180,6 +180,7 @@ SOKOL_API_DECL uint32_t sfons_rgba(uint8_t r, uint8_t g, uint8_t b, uint8_t a);
 #ifdef __cplusplus
 } /* extern "C" */
 #endif
+#endif /* SOKOL_FONTSTASH_INCLUDED */
 
 /*-- IMPLEMENTATION ----------------------------------------------------------*/
 #ifdef SOKOL_FONTSTASH_IMPL

util/sokol_gfx_imgui.h

@@ -1,4 +1,4 @@
-#pragma once
+#ifndef SOKOL_GFX_IMGUI_INCLUDED
 /*
     sokol_gfx_imgui.h -- debug-inspection UI for sokol_gfx.h using Dear ImGui
 
@@ -157,6 +157,7 @@
         3. This notice may not be removed or altered from any source
         distribution.
 */
+#define SOKOL_GFX_IMGUI_INCLUDED (1)
 #include <stdint.h>
 #include <stdbool.h>
 
@@ -583,9 +584,11 @@ SOKOL_API_DECL void sg_imgui_draw_capabilities_window(sg_imgui_t* ctx);
 #if defined(__cplusplus)
 } /* extern "C" */
 #endif
+#endif /* SOKOL_GFX_IMGUI_INCLUDED */
 
 /*=== IMPLEMENTATION =========================================================*/
-#if defined SOKOL_GFX_IMGUI_IMPL
+#ifdef SOKOL_GFX_IMGUI_IMPL
+#define SOKOL_GFX_IMGUI_IMPL_INCLUDED (1)
 #if defined(__cplusplus)
     #if !defined(IMGUI_VERSION)
     #error "Please include imgui.h before the sokol_imgui.h implementation"

util/sokol_gl.h

@@ -1,4 +1,4 @@
-#pragma once
+#ifndef SOKOL_GL_INCLUDED
 /*
     sokol_gl.h -- OpenGL 1.x style rendering on top of sokol_gfx.h
 
@@ -298,7 +298,8 @@
             sgl_end()
 
         This will record a new draw command in sokol-gl's internal command
-        list.
+        list, or it will extend the previous draw command if no relevant
+        state has changed since the last sgl_begin/end pair.
 
     --- inside a sokol-gfx rendering pass, call:
 
@@ -386,10 +387,30 @@
                       sg_apply_uniforms()
                     - finally call sg_draw()
 
-    All other functions just modify the internally tracked state, add
+    All other functions only modify the internally tracked state, add
     data to the vertex, uniform and command buffers, or manipulate
     the matrix stack.
 
+    ON DRAW COMMAND MERGING
+    =======================
+    Not every call to sgl_end() will automatically record a new draw command.
+    If possible, the previous draw command will simply be extended,
+    resulting in fewer actual draw calls later in sgl_draw().
+
+    A draw command will be merged with the previous command if "no relevant
+    state has changed" since the last sgl_end(), meaning:
+
+    - no calls to sgl_apply_viewport() and sgl_apply_scissor_rect()
+    - the primitive type hasn't changed
+    - the primitive type isn't a 'strip type' (no line or triangle strip)
+    - the pipeline state object hasn't changed
+    - none of the matrices has changed
+    - none of the texture state has changed
+
+    Merging a draw command simply means that the number of vertices
+    to render in the previous draw command will be incremented by the
+    number of vertices in the new draw command.
+
     LICENSE
     =======
     zlib/libpng license
@@ -556,6 +577,7 @@ SOKOL_API_DECL void sgl_draw(void);
 #ifdef __cplusplus
 } /* extern "C" */
 #endif
+#endif /* SOKOL_GL_INCLUDED */
 
 /*-- IMPLEMENTATION ----------------------------------------------------------*/
 #ifdef SOKOL_GL_IMPL

util/sokol_imgui.h

@@ -1,4 +1,4 @@
-#pragma once
+#ifndef SOKOL_IMGUI_INCLUDED
 /*
     sokol_imgui.h -- drop-in Dear ImGui renderer/event-handler for sokol_gfx.h
 
@@ -232,6 +232,7 @@ SOKOL_API_DECL void simgui_shutdown(void);
 #ifdef __cplusplus
 } /* extern "C" */
 #endif
+#endif /* SOKOL_IMGUI_INCLUDED */
 
 /*-- IMPLEMENTATION ----------------------------------------------------------*/
 #ifdef SOKOL_IMGUI_IMPL