Method useProgram

src/main/java/net/optifine/shaders/Shaders.java:3286–3494

(Program program)

    }

    public static void useProgram(Program program)
    {
        checkGLError("pre-useProgram");

        if (isShadowPass)
        {
            program = ProgramShadow;
        }
        else if (isEntitiesGlowing)
        {
            program = ProgramEntitiesGlowing;
        }

        if (activeProgram != program)
        {
            updateAlphaBlend(activeProgram, program);
            activeProgram = program;
            int i = program.getId();
            activeProgramID = i;
            ARBShaderObjects.glUseProgramObjectARB(i);

            if (checkGLError("useProgram") != 0)
            {
                program.setId(0);
                i = program.getId();
                activeProgramID = i;
                ARBShaderObjects.glUseProgramObjectARB(i);
            }

            shaderUniforms.setProgram(i);

            if (customUniforms != null)
            {
                customUniforms.setProgram(i);
            }

            if (i != 0)
            {
                IntBuffer intbuffer = program.getDrawBuffers();

                if (isRenderingDfb)
                {
                    setDrawBuffers(intbuffer);
                }

                activeCompositeMipmapSetting = program.getCompositeMipmapSetting();

                switch (program.getProgramStage())
                {
                    case GBUFFERS:
                        setProgramUniform1i(uniform_texture, 0);
                        setProgramUniform1i(uniform_lightmap, 1);
                        setProgramUniform1i(uniform_normals, 2);
                        setProgramUniform1i(uniform_specular, 3);
                        setProgramUniform1i(uniform_shadow, waterShadowEnabled ? 5 : 4);
                        setProgramUniform1i(uniform_watershadow, 4);
                        setProgramUniform1i(uniform_shadowtex0, 4);
                        setProgramUniform1i(uniform_shadowtex1, 5);