Renamed sdlgpu to gpu

src/render/gpu/shaders/texture_rgb.frag

@@ -0,0 +1,12 @@
+#version 450
+
+layout(location = 0) in vec4 v_color;
+layout(location = 1) in vec2 v_uv;
+
+layout(set = 2, binding = 0) uniform sampler2D u_texture;
+
+layout(location = 0) out vec4 o_color;
+
+void main() {
+    o_color = vec4(texture(u_texture, v_uv).rgb, 1) * v_color;
+}