Cleanup: GPU: Set default GL_UNPACK_ALIGNMENT to 1

Ogl default is 4 but for almost all cases, blender use tightly
packed format. This avoid confusion and state change for the
common case.

The only case that __might__ need alignement is DDS loader
(untested) so leaving this as it is.

4 files changed, 7 insertions, 19 deletions

diff --git a/source/blender/gpu/intern/gpu_draw.c b/source/blender/gpu/intern/gpu_draw.c
index 7e6d47636f6..9fdb98cfbf6 100644
--- a/source/blender/gpu/intern/gpu_draw.c
+++ b/source/blender/gpu/intern/gpu_draw.c
@@ -1195,6 +1195,9 @@ bool GPU_upload_dxt_texture(ImBuf *ibuf, bool use_srgb)
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, gpu_get_mipmap_filter(0));
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, gpu_get_mipmap_filter(1));
 
+  /* Reset to opengl Defaults. (Untested, might not be needed) */
+  glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
+
   blocksize = (ibuf->dds_data.fourcc == FOURCC_DXT1) ? 8 : 16;
   for (i = 0; i < ibuf->dds_data.nummipmaps && (width || height); i++) {
     if (width == 0) {
@@ -1213,6 +1216,8 @@ bool GPU_upload_dxt_texture(ImBuf *ibuf, bool use_srgb)
     width >>= 1;
     height >>= 1;
   }
+  /* Restore Blender default. */
+  glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 
   /* set number of mipmap levels we have, needed in case they don't go down to 1x1 */
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, i - 1);
diff --git a/source/blender/gpu/intern/gpu_state.c b/source/blender/gpu/intern/gpu_state.c
index 636a5e2c31d..b52504eb492 100644
--- a/source/blender/gpu/intern/gpu_state.c
+++ b/source/blender/gpu/intern/gpu_state.c
@@ -412,6 +412,8 @@ void GPU_state_init(void)
   glCullFace(GL_BACK);
   glDisable(GL_CULL_FACE);
 
+  glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+
   /* Is default but better be explicit. */
   glEnable(GL_MULTISAMPLE);
 
diff --git a/source/blender/gpu/intern/gpu_texture.c b/source/blender/gpu/intern/gpu_texture.c
index c4d7eccf9f9..4c847236f09 100644
--- a/source/blender/gpu/intern/gpu_texture.c
+++ b/source/blender/gpu/intern/gpu_texture.c
@@ -1465,16 +1465,8 @@ void GPU_texture_update_sub(GPUTexture *tex,
   BLI_assert((int)tex->format > -1);
   BLI_assert(tex->components > -1);
 
-  const uint bytesize = gpu_get_bytesize(tex->format);
   GLenum data_format = gpu_get_gl_dataformat(tex->format, &tex->format_flag);
   GLenum data_type = gpu_get_gl_datatype(gpu_data_format);
-  GLint alignment;
-
-  /* The default pack size for textures is 4, which won't work for byte based textures */
-  if (bytesize == 1) {
-    glGetIntegerv(GL_UNPACK_ALIGNMENT, &alignment);
-    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
-  }
 
   glBindTexture(tex->target, tex->bindcode);
   switch (tex->target) {
@@ -1505,10 +1497,6 @@ void GPU_texture_update_sub(GPUTexture *tex,
       BLI_assert(!"tex->target mode not supported");
   }
 
-  if (bytesize == 1) {
-    glPixelStorei(GL_UNPACK_ALIGNMENT, alignment);
-  }
-
   glBindTexture(tex->target, 0);
 }
 
diff --git a/source/blender/windowmanager/intern/wm_gesture.c b/source/blender/windowmanager/intern/wm_gesture.c
index 52c934424e4..e7cb1c00605 100644
--- a/source/blender/windowmanager/intern/wm_gesture.c
+++ b/source/blender/windowmanager/intern/wm_gesture.c
@@ -357,11 +357,6 @@ static void draw_filled_lasso(wmGesture *gt)
     GPU_blend(true);
     GPU_blend_set_func(GPU_ONE, GPU_ONE);
 
-    GLint unpack_alignment;
-    glGetIntegerv(GL_UNPACK_ALIGNMENT, &unpack_alignment);
-
-    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
-
     IMMDrawPixelsTexState state = immDrawPixelsTexSetup(GPU_SHADER_2D_IMAGE_SHUFFLE_COLOR);
     GPU_shader_bind(state.shader);
     GPU_shader_uniform_vector(
@@ -382,8 +377,6 @@ static void draw_filled_lasso(wmGesture *gt)
 
     GPU_shader_unbind();
 
-    glPixelStorei(GL_UNPACK_ALIGNMENT, unpack_alignment);
-
     MEM_freeN(pixel_buf);
 
     GPU_blend(false);