[Scummvm-git-logs] scummvm master -> 675bea8c868cf69999ead03dbd2c27bae02bccf5

[aquadran]

This automated email contains information about 1 new commit which have been
pushed to the 'scummvm' repo located at https://api.github.com/repos/scummvm/scummvm .

Summary:
675bea8c86 EMI: Don't overwrite global actor alpha when drawing sprites


Commit: 675bea8c868cf69999ead03dbd2c27bae02bccf5
    https://github.com/scummvm/scummvm/commit/675bea8c868cf69999ead03dbd2c27bae02bccf5
Author: Christian Krause (chkr at plauener.de)
Date: 2025-11-22T07:54:17+01:00

Commit Message:
EMI: Don't overwrite global actor alpha when drawing sprites

- currently, with the shader renderer, the bananas in the
  monkey combat scene never vanish
- the reason is, that the actor's global alpha value is set
  via uniformColor in startActorDraw() but is overwritten
  in drawSprite()
- set the sprite's color (and alpha) values using a different
  uniform variable and multiply them in the sprite's vertex
  shader

Changed paths:
    engines/grim/gfx_opengl_shaders.cpp
    engines/grim/shaders/emi_sprite.vertex


diff --git a/engines/grim/gfx_opengl_shaders.cpp b/engines/grim/gfx_opengl_shaders.cpp
index 19169c6a3f2..f4feea6dd03 100644
--- a/engines/grim/gfx_opengl_shaders.cpp
+++ b/engines/grim/gfx_opengl_shaders.cpp
@@ -1172,7 +1172,13 @@ void GfxOpenGLS::drawSprite(const Sprite *sprite) {
 	// FIXME: Currently vertex-specific colors are not supported for sprites.
 	// It is unknown at this time if this is really needed anywhere.
 	Math::Vector4d color(sprite->_red[0] / 255.0f, sprite->_green[0] / 255.0f, sprite->_blue[0] / 255.0f, sprite->_alpha[0] / 255.0f);
-	_spriteProgram->setUniform("uniformColor", color);
+	if (g_grim->getGameType() == GType_MONKEY4) {
+		// Don't overwrite the actor's alpha value  which is set via uniformColor in startActorDraw()
+		_spriteProgram->setUniform("spriteColor", color);
+	} else {
+		// No need to set spriteColor for GRIM, it is specific to the EMI sprite shader program
+		_spriteProgram->setUniform("uniformColor", color);
+	}
 
 	float sprite_textured_quad[] = {
 	//	 X   ,  Y   , Z   , S   , T
diff --git a/engines/grim/shaders/emi_sprite.vertex b/engines/grim/shaders/emi_sprite.vertex
index 51f1bb86464..90855b73b74 100644
--- a/engines/grim/shaders/emi_sprite.vertex
+++ b/engines/grim/shaders/emi_sprite.vertex
@@ -12,6 +12,7 @@ uniform highp vec3 cameraPos;
 uniform UBOOL textured;
 uniform UBOOL useVertexAlpha;
 uniform vec4 uniformColor;
+uniform vec4 spriteColor;
 
 struct shadow_info {
 	UBOOL _active;
@@ -49,6 +50,7 @@ void main() {
 	if (!UBOOL_TEST(useVertexAlpha))
 		Color.a = 1.0;
 	Color *= uniformColor;
+	Color *= spriteColor;
 	if (UBOOL_TEST(textured)) {
 		Texcoord = texcoord;
 	} else {