Make image drawing code working with core profile

The issue was caused here by usage of deprecated GL_CURRENT_PROGRAM
which was returning rubbish value.

Now we use imm API and create vertex format prior to immBindProgram.
This made us required to have some sort of state passed from setup
function to actual drawing.

1 files changed, 45 insertions, 31 deletions

diff --git a/source/blender/editors/screen/glutil.c b/source/blender/editors/screen/glutil.c
index 7387d9481d5..233ecf8c83d 100644
--- a/source/blender/editors/screen/glutil.c
+++ b/source/blender/editors/screen/glutil.c
@@ -137,19 +137,33 @@ static int get_cached_work_texture(int *r_w, int *r_h)
 	return texid;
 }
 
+static void immDrawPixelsTexSetupAttributes(IMMDrawPixelsTexState *state)
+{
+	VertexFormat *vert_format = immVertexFormat();
+	unsigned int pos = VertexFormat_add_attrib(vert_format, "pos", COMP_F32, 2, KEEP_FLOAT);
+	unsigned int texco = VertexFormat_add_attrib(vert_format, "texCoord", COMP_F32, 2, KEEP_FLOAT);
+	state->pos = pos;
+	state->texco = texco;
+}
+
 /* To be used before calling immDrawPixelsTex
  * Default shader is GPU_SHADER_2D_IMAGE_COLOR
  * You can still set uniforms with :
  * GPU_shader_uniform_int(shader, GPU_shader_get_uniform(shader, "name"), 0);
  * */
-GPUShader *immDrawPixelsTexSetup(int builtin)
+IMMDrawPixelsTexState immDrawPixelsTexSetup(int builtin)
 {
+	IMMDrawPixelsTexState state;
+	immDrawPixelsTexSetupAttributes(&state);
+
 	GPUShader *shader = GPU_shader_get_builtin_shader(builtin);
 	/* Shader will be unbind by immUnbindProgram in immDrawPixelsTexScaled_clipping */
-	GPU_shader_bind(shader);
+	immBindBuiltinProgram(builtin);
 	GPU_shader_uniform_int(shader, GPU_shader_get_uniform(shader, "image"), 0);
 
-	return shader;
+	state.shader = shader;
+
+	return state;
 }
 
 /* Use the currently bound shader.
@@ -165,7 +179,8 @@ GPUShader *immDrawPixelsTexSetup(int builtin)
  * Be also aware that this function unbinds the shader when
  * it's finished.
  * */
-void immDrawPixelsTexScaled_clipping(float x, float y, int img_w, int img_h,
+void immDrawPixelsTexScaled_clipping(IMMDrawPixelsTexState *state,
+                                     float x, float y, int img_w, int img_h,
                                      int format, int type, int zoomfilter, void *rect,
                                      float scaleX, float scaleY,
                                      float clip_min_x, float clip_min_y,
@@ -229,25 +244,15 @@ void immDrawPixelsTexScaled_clipping(float x, float y, int img_w, int img_h,
 		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, tex_w, tex_h, 0, format, GL_UNSIGNED_BYTE, NULL);
 	}
 
-	VertexFormat *vert_format = immVertexFormat();
-	unsigned int pos = VertexFormat_add_attrib(vert_format, "pos", COMP_F32, 2, KEEP_FLOAT);
-	unsigned int texco = VertexFormat_add_attrib(vert_format, "texCoord", COMP_F32, 2, KEEP_FLOAT);
-
-	unsigned int program = glaGetOneInt(GL_CURRENT_PROGRAM);
-
-	/* This is needed for the OCIO case.
-	 * Shader program is set outside of blender and
-	 * we need it in imm module to do all attrib /
-	 * uniform bindings. */
+	unsigned int pos = 0, texco = 1;
 
-	/* A program is already bound.
-	 * set it in imm.bound_program to be able to use imm functions */
-	BLI_assert(program);
-	immBindProgram(program);
-
-	/* optionnal */
-	if (glGetUniformLocation(program, "color") != -1)
+	/* optional */
+	/* NOTE: Shader could be null for GLSL OCIO drawing, it is fine, since
+	 * it does not need color.
+	 */
+	if (state->shader != NULL && GPU_shader_get_uniform(state->shader, "color") != -1) {
 		immUniform4fv("color", (color) ? color : white);
+	}
 
 	for (subpart_y = 0; subpart_y < nsubparts_y; subpart_y++) {
 		for (subpart_x = 0; subpart_x < nsubparts_x; subpart_x++) {
@@ -322,27 +327,30 @@ void immDrawPixelsTexScaled_clipping(float x, float y, int img_w, int img_h,
 	glPixelStorei(GL_UNPACK_ROW_LENGTH, unpack_row_length);
 }
 
-void immDrawPixelsTexScaled(float x, float y, int img_w, int img_h,
+void immDrawPixelsTexScaled(IMMDrawPixelsTexState *state,
+                            float x, float y, int img_w, int img_h,
                             int format, int type, int zoomfilter, void *rect,
                             float scaleX, float scaleY, float xzoom, float yzoom, float color[4])
 {
-	immDrawPixelsTexScaled_clipping(x, y, img_w, img_h, format, type, zoomfilter, rect,
+	immDrawPixelsTexScaled_clipping(state, x, y, img_w, img_h, format, type, zoomfilter, rect,
 	                                scaleX, scaleY, 0.0f, 0.0f, 0.0f, 0.0f, xzoom, yzoom, color);
 }
 
-void immDrawPixelsTex(float x, float y, int img_w, int img_h, int format, int type, int zoomfilter, void *rect,
+void immDrawPixelsTex(IMMDrawPixelsTexState *state,
+                      float x, float y, int img_w, int img_h, int format, int type, int zoomfilter, void *rect,
                       float xzoom, float yzoom, float color[4])
 {
-	immDrawPixelsTexScaled_clipping(x, y, img_w, img_h, format, type, zoomfilter, rect, 1.0f, 1.0f,
+	immDrawPixelsTexScaled_clipping(state, x, y, img_w, img_h, format, type, zoomfilter, rect, 1.0f, 1.0f,
 	                                0.0f, 0.0f, 0.0f, 0.0f, xzoom, yzoom, color);
 }
 
-void immDrawPixelsTex_clipping(float x, float y, int img_w, int img_h,
+void immDrawPixelsTex_clipping(IMMDrawPixelsTexState *state,
+                               float x, float y, int img_w, int img_h,
                                int format, int type, int zoomfilter, void *rect,
                                float clip_min_x, float clip_min_y, float clip_max_x, float clip_max_y,
                                float xzoom, float yzoom, float color[4])
 {
-	immDrawPixelsTexScaled_clipping(x, y, img_w, img_h, format, type, zoomfilter, rect, 1.0f, 1.0f,
+	immDrawPixelsTexScaled_clipping(state, x, y, img_w, img_h, format, type, zoomfilter, rect, 1.0f, 1.0f,
 	                                clip_min_x, clip_min_y, clip_max_x, clip_max_y, xzoom, yzoom, color);
 }
 
@@ -575,6 +583,9 @@ void glaDrawImBuf_glsl_clipping(ImBuf *ibuf, float x, float y, int zoomfilter,
 	if (force_fallback == false) {
 		int ok;
 
+		IMMDrawPixelsTexState state = {0};
+		immDrawPixelsTexSetupAttributes(&state);
+
 		if (ibuf->rect_float) {
 			if (ibuf->float_colorspace) {
 				ok = IMB_colormanagement_setup_glsl_draw_from_space(view_settings, display_settings,
@@ -604,7 +615,8 @@ void glaDrawImBuf_glsl_clipping(ImBuf *ibuf, float x, float y, int zoomfilter,
 					BLI_assert(!"Incompatible number of channels for GLSL display");
 
 				if (format != 0) {
-					immDrawPixelsTex_clipping(x, y, ibuf->x, ibuf->y, format, GL_FLOAT,
+					immDrawPixelsTex_clipping(&state,
+					                          x, y, ibuf->x, ibuf->y, format, GL_FLOAT,
 					                          zoomfilter, ibuf->rect_float,
 					                          clip_min_x, clip_min_y, clip_max_x, clip_max_y,
 					                          zoom_x, zoom_y, NULL);
@@ -612,7 +624,8 @@ void glaDrawImBuf_glsl_clipping(ImBuf *ibuf, float x, float y, int zoomfilter,
 			}
 			else if (ibuf->rect) {
 				/* ibuf->rect is always RGBA */
-				immDrawPixelsTex_clipping(x, y, ibuf->x, ibuf->y, GL_RGBA, GL_UNSIGNED_BYTE,
+				immDrawPixelsTex_clipping(&state,
+				                          x, y, ibuf->x, ibuf->y, GL_RGBA, GL_UNSIGNED_BYTE,
 				                          zoomfilter, ibuf->rect,
 				                          clip_min_x, clip_min_y, clip_max_x, clip_max_y,
 				                          zoom_x, zoom_y, NULL);
@@ -632,8 +645,9 @@ void glaDrawImBuf_glsl_clipping(ImBuf *ibuf, float x, float y, int zoomfilter,
 		display_buffer = IMB_display_buffer_acquire(ibuf, view_settings, display_settings, &cache_handle);
 
 		if (display_buffer) {
-			immDrawPixelsTexSetup(GPU_SHADER_2D_IMAGE_COLOR);
-			immDrawPixelsTex_clipping(x, y, ibuf->x, ibuf->y, GL_RGBA, GL_UNSIGNED_BYTE,
+			IMMDrawPixelsTexState state = immDrawPixelsTexSetup(GPU_SHADER_2D_IMAGE_COLOR);
+			immDrawPixelsTex_clipping(&state,
+			                          x, y, ibuf->x, ibuf->y, GL_RGBA, GL_UNSIGNED_BYTE,
 			                          zoomfilter, display_buffer,
 			                          clip_min_x, clip_min_y, clip_max_x, clip_max_y,
 			                          zoom_x, zoom_y, NULL);