VIGS: Use glTexSubImage2D instead of glDrawPixels

With some GPUs (like Intel HD Graphics 2000) glDrawPixels
with glPixelZoom doesn't work very well, it may do
software fallback or produce ban rendering, so it's
better to use glTexSubImage2D

Change-Id: I827f0985d558493067954a95c05e227dc064fe88

diff --git a/hw/vigs/vigs_gl_backend.c b/hw/vigs/vigs_gl_backend.c
index 7529b4b..2cf7a94 100644 (file)
--- a/hw/vigs/vigs_gl_backend.c
+++ b/hw/vigs/vigs_gl_backend.c
@@ -443,28 +443,30 @@ static void vigs_gl_surface_draw_pixels(struct vigs_surface *sfc,
     struct vigs_gl_backend *gl_backend = (struct vigs_gl_backend*)sfc->backend;
     struct vigs_gl_surface *gl_sfc = (struct vigs_gl_surface*)sfc;
     struct vigs_winsys_gl_surface *ws_sfc = get_ws_sfc(gl_sfc);
+    GLfloat sfc_w, sfc_h;
+    GLfloat *vert_coords;
+    GLfloat *tex_coords;
     uint32_t i;
 
     if (!vigs_winsys_gl_surface_create_texture(ws_sfc, &ws_sfc->tex)) {
         goto out;
     }
 
-    if (!vigs_gl_surface_create_framebuffer(gl_sfc)) {
+    if (!vigs_winsys_gl_surface_create_texture(ws_sfc, &gl_sfc->tmp_tex)) {
         goto out;
     }
 
-    gl_backend->BindFramebuffer(GL_FRAMEBUFFER, gl_sfc->fb);
-
-    vigs_gl_surface_setup_framebuffer(gl_sfc);
+    if (!vigs_gl_surface_create_framebuffer(gl_sfc)) {
+        goto out;
+    }
 
-    gl_backend->Disable(GL_TEXTURE_2D);
+    sfc_w = ws_sfc->base.base.width;
+    sfc_h = ws_sfc->base.base.height;
 
-    gl_backend->FramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
-                                     GL_TEXTURE_2D, ws_sfc->tex, 0);
+    gl_backend->BindTexture(GL_TEXTURE_2D, gl_sfc->tmp_tex);
 
-    gl_backend->PixelZoom(1.0f, -1.0f);
     gl_backend->PixelStorei(GL_UNPACK_ALIGNMENT, 1);
-    gl_backend->PixelStorei(GL_UNPACK_ROW_LENGTH, ws_sfc->base.base.width);
+    gl_backend->PixelStorei(GL_UNPACK_ROW_LENGTH, sfc_w);
 
     for (i = 0; i < num_entries; ++i) {
         uint32_t x = entries[i].pos.x;
@@ -476,14 +478,65 @@ static void vigs_gl_surface_draw_pixels(struct vigs_surface *sfc,
                        width, height);
         gl_backend->PixelStorei(GL_UNPACK_SKIP_PIXELS, x);
         gl_backend->PixelStorei(GL_UNPACK_SKIP_ROWS, y);
-        gl_backend->WindowPos2f(x, ws_sfc->base.base.height - y);
-        gl_backend->DrawPixels(width,
-                               height,
-                               ws_sfc->tex_format,
-                               ws_sfc->tex_type,
-                               pixels);
+        gl_backend->TexSubImage2D(GL_TEXTURE_2D, 0, x, y,
+                                  width, height,
+                                  ws_sfc->tex_format,
+                                  ws_sfc->tex_type,
+                                  pixels);
     }
 
+    vigs_vector_resize(&gl_backend->v1, 0);
+    vigs_vector_resize(&gl_backend->v2, 0);
+
+    gl_backend->BindFramebuffer(GL_FRAMEBUFFER, gl_sfc->fb);
+
+    vigs_gl_surface_setup_framebuffer(gl_sfc);
+
+    gl_backend->Enable(GL_TEXTURE_2D);
+
+    gl_backend->FramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
+                                     GL_TEXTURE_2D, ws_sfc->tex, 0);
+
+    for (i = 0; i < num_entries; ++i) {
+        vert_coords = vigs_vector_append(&gl_backend->v1,
+                                         (8 * sizeof(GLfloat)));
+        tex_coords = vigs_vector_append(&gl_backend->v2,
+                                        (8 * sizeof(GLfloat)));
+
+        vert_coords[0] = entries[i].pos.x;
+        vert_coords[1] = sfc_h - entries[i].pos.y;
+        vert_coords[2] = entries[i].pos.x + entries[i].size.w;
+        vert_coords[3] = sfc_h - entries[i].pos.y;
+        vert_coords[4] = entries[i].pos.x + entries[i].size.w;
+        vert_coords[5] = sfc_h - (entries[i].pos.y + entries[i].size.h);
+        vert_coords[6] = entries[i].pos.x;
+        vert_coords[7] = sfc_h - (entries[i].pos.y + entries[i].size.h);
+
+        tex_coords[0] = (GLfloat)entries[i].pos.x / sfc_w;
+        tex_coords[1] = (GLfloat)entries[i].pos.y / sfc_h;
+        tex_coords[2] = (GLfloat)(entries[i].pos.x + entries[i].size.w) / sfc_w;
+        tex_coords[3] = (GLfloat)entries[i].pos.y / sfc_h;
+        tex_coords[4] = (GLfloat)(entries[i].pos.x + entries[i].size.w) / sfc_w;
+        tex_coords[5] = (GLfloat)(entries[i].pos.y + entries[i].size.h) / sfc_h;
+        tex_coords[6] = (GLfloat)entries[i].pos.x / sfc_w;
+        tex_coords[7] = (GLfloat)(entries[i].pos.y + entries[i].size.h) / sfc_h;
+    }
+
+    gl_backend->EnableClientState(GL_VERTEX_ARRAY);
+    gl_backend->EnableClientState(GL_TEXTURE_COORD_ARRAY);
+
+    gl_backend->BindTexture(GL_TEXTURE_2D, gl_sfc->tmp_tex);
+
+    gl_backend->Color4f(1.0f, 1.0f, 1.0f, 1.0f);
+
+    gl_backend->VertexPointer(2, GL_FLOAT, 0, vigs_vector_data(&gl_backend->v1));
+    gl_backend->TexCoordPointer(2, GL_FLOAT, 0, vigs_vector_data(&gl_backend->v2));
+
+    gl_backend->DrawArrays(GL_QUADS, 0, num_entries * 4);
+
+    gl_backend->DisableClientState(GL_TEXTURE_COORD_ARRAY);
+    gl_backend->DisableClientState(GL_VERTEX_ARRAY);
+
 out:
     gl_backend->BindFramebuffer(GL_FRAMEBUFFER, 0);
 }