Use correct alpha blending for transparent windowHEADmaster

7 files changed, 4 insertions, 31 deletions

diff --git a/include/mgl/gl.h b/include/mgl/gl.h
index 87a3ccd..4658198 100644
--- a/include/mgl/gl.h
+++ b/include/mgl/gl.h
@@ -58,6 +58,7 @@ typedef struct {
     void (*glClear)(unsigned int mask);
     void (*glEnable)(unsigned int cap);
     void (*glBlendFunc)(unsigned int sfactor, unsigned int dfactor);
+    void (*glBlendFuncSeparate)(unsigned int sfactorRGB, unsigned int dfactorRGB, unsigned int sfactorAlpha, unsigned int dfactorAlpha);
     void (*glGenTextures)(int n, unsigned int *textures);
     void (*glDeleteTextures)(int n, const unsigned int *textures);
     void (*glGetTexLevelParameteriv)(unsigned int target, int level, unsigned int pname, int *params);
diff --git a/include/mgl/window/window.h b/include/mgl/window/window.h
index 77589c9..a5ccbf7 100644
--- a/include/mgl/window/window.h
+++ b/include/mgl/window/window.h
@@ -81,7 +81,7 @@ typedef struct {
     mgl_window_handle parent_window;         /* 0 = root window */
     bool hidden;                             /* false by default */
     bool override_redirect;                  /* false by default */
-    bool support_alpha;                      /* support alpha for the window, false by default. If this is set to true then you need to call mgl_window_set_texture_blend_func before rendering textures and call mgl_window_set_render_blend_func afterwards to ensure correct alpha blending */
+    bool support_alpha;                      /* support alpha for the window, false by default */
     bool hide_decorations;                   /* this is a hint, it may be ignored by the window manager, false by default */
     mgl_color background_color;              /* default: black */
     const char *class_name;
@@ -182,9 +182,6 @@ bool mgl_window_get_clipboard(mgl_window *self, mgl_clipboard_callback callback,
 bool mgl_window_get_clipboard_string(mgl_window *self, char **str, size_t *size);
 void mgl_window_set_key_repeat_enabled(mgl_window *self, bool enabled);
 
-void mgl_window_set_texture_blend_func(mgl_window *self);
-void mgl_window_set_render_blend_func(mgl_window *self);
-
 void mgl_window_flush(mgl_window *self);
 
 void* mgl_window_get_egl_display(mgl_window *self);
diff --git a/src/gl.c b/src/gl.c
index bb2e90b..b5cb256 100644
--- a/src/gl.c
+++ b/src/gl.c
@@ -27,6 +27,7 @@ static int mgl_gl_load_gl(mgl_gl *self) {
         { (void**)&self->glClear, "glClear" },
         { (void**)&self->glEnable, "glEnable" },
         { (void**)&self->glBlendFunc, "glBlendFunc" },
+        { (void**)&self->glBlendFuncSeparate, "glBlendFuncSeparate" },
         { (void**)&self->glGenTextures, "glGenTextures" },
         { (void**)&self->glDeleteTextures, "glDeleteTextures" },
         { (void**)&self->glGetTexLevelParameteriv, "glGetTexLevelParameteriv" },
diff --git a/src/graphics/sprite.c b/src/graphics/sprite.c
index ce2566e..7ef81af 100644
--- a/src/graphics/sprite.c
+++ b/src/graphics/sprite.c
@@ -1,6 +1,5 @@
 #include "../../include/mgl/graphics/sprite.h"
 #include "../../include/mgl/graphics/texture.h"
-#include "../../include/mgl/window/window.h"
 #include "../../include/mgl/mgl.h"
 
 void mgl_sprite_init(mgl_sprite *self, mgl_texture *texture) {
@@ -69,8 +68,6 @@ void mgl_sprite_draw(mgl_context *context, mgl_sprite *sprite) {
     if(!sprite->texture)
         return;
 
-    mgl_window_set_texture_blend_func(context->current_window);
-
     float texture_right = 1.0f;
     float texture_bottom = 1.0f;
     if(sprite->texture->pixel_coordinates) {
@@ -97,6 +94,4 @@ void mgl_sprite_draw(mgl_context *context, mgl_sprite *sprite) {
     context->gl.glEnd();
     mgl_texture_use(NULL);
     context->gl.glLoadIdentity(); /* TODO: Remove, but what about glRotatef above */
-
-    mgl_window_set_render_blend_func(context->current_window);
 }
diff --git a/src/graphics/text.c b/src/graphics/text.c
index 0280edb..2aa3bb4 100644
--- a/src/graphics/text.c
+++ b/src/graphics/text.c
@@ -1,7 +1,6 @@
 #include "../../include/mgl/graphics/text.h"
 #include "../../include/mgl/graphics/font.h"
 #include "../../include/mgl/system/utf8.h"
-#include "../../include/mgl/window/window.h"
 #include "../../include/mgl/mgl.h"
 #include <stdio.h>
 
@@ -248,14 +247,10 @@ void mgl_text_draw(mgl_context *context, mgl_text *text) {
     text_draw_userdata.text = text;
     text_draw_userdata.context = context;
 
-    mgl_window_set_texture_blend_func(context->current_window);
-
     context->gl.glColor4ub(text->color.r, text->color.g, text->color.b, text->color.a);
     mgl_texture_use(&text->font->texture);
     context->gl.glBegin(GL_QUADS);
     mgl_text_for_each_codepoint(text, text_draw_callback, &text_draw_userdata);
     context->gl.glEnd();
     mgl_texture_use(NULL);
-
-    mgl_window_set_render_blend_func(context->current_window);
 }
diff --git a/src/graphics/vertex.c b/src/graphics/vertex.c
index 92a6e93..e55c180 100644
--- a/src/graphics/vertex.c
+++ b/src/graphics/vertex.c
@@ -1,14 +1,11 @@
 #include "../../include/mgl/graphics/vertex.h"
 #include "../../include/mgl/graphics/texture.h"
-#include "../../include/mgl/window/window.h"
 #include "../../include/mgl/mgl.h"
 
 void mgl_vertices_draw(mgl_context *context, const mgl_vertex *vertices, size_t vertex_count, mgl_primitive_type primitive_type, mgl_vec2f position) {
     if(vertex_count == 0)
         return;
 
-    mgl_window_set_texture_blend_func(context->current_window);
-
     context->gl.glPushMatrix();
 
     if(!mgl_texture_current_texture()) {
@@ -25,6 +22,4 @@ void mgl_vertices_draw(mgl_context *context, const mgl_vertex *vertices, size_t
     context->gl.glDrawArrays(mgl_primitive_type_to_gl_mode(primitive_type), 0, vertex_count);
 
     context->gl.glPopMatrix();
-
-    mgl_window_set_render_blend_func(context->current_window);
 }
diff --git a/src/window/window.c b/src/window/window.c
index dd91110..d931a9f 100644
--- a/src/window/window.c
+++ b/src/window/window.c
@@ -1017,7 +1017,7 @@ static int mgl_window_init(mgl_window *self, const char *title, const mgl_window
     context->gl.glEnable(GL_TEXTURE_2D);
     context->gl.glEnable(GL_BLEND);
     context->gl.glEnable(GL_SCISSOR_TEST);
-    mgl_window_set_render_blend_func(self);
+    context->gl.glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
     context->gl.glEnableClientState(GL_VERTEX_ARRAY);
     context->gl.glEnableClientState(GL_TEXTURE_COORD_ARRAY);
     context->gl.glEnableClientState(GL_COLOR_ARRAY);
@@ -2120,17 +2120,6 @@ void mgl_window_set_key_repeat_enabled(mgl_window *self, bool enabled) {
     self->key_repeat_enabled = enabled;
 }
 
-void mgl_window_set_texture_blend_func(mgl_window *self) {
-    mgl_context *context = mgl_get_context();
-    context->gl.glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-}
-
-void mgl_window_set_render_blend_func(mgl_window *self) {
-    mgl_context *context = mgl_get_context();
-    x11_context *x11_context = self->context;
-    context->gl.glBlendFunc(x11_context->support_alpha ? GL_ONE : GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-}
-
 void mgl_window_flush(mgl_window *self) {
     mgl_context *context = mgl_get_context();
     XFlush(context->connection);