From 34c7c1838aa0e410ee9b62f8a04ed8b48e6a968b Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Wed, 20 Oct 1999 22:32:02 +0000 Subject: fixed divTable precision problem in GL_RETURN case --- src/mesa/main/accum.c | 74 ++++++++++++++++++++++++++++++++------------------- 1 file changed, 46 insertions(+), 28 deletions(-) (limited to 'src') diff --git a/src/mesa/main/accum.c b/src/mesa/main/accum.c index b7bb3f6e854..de660a84a6a 100644 --- a/src/mesa/main/accum.c +++ b/src/mesa/main/accum.c @@ -1,4 +1,4 @@ -/* $Id: accum.c,v 1.6 1999/10/13 18:42:49 brianp Exp $ */ +/* $Id: accum.c,v 1.7 1999/10/20 22:32:02 brianp Exp $ */ /* * Mesa 3-D graphics library @@ -74,6 +74,9 @@ */ +#define USE_OPTIMIZED_ACCUM /* enable the optimization */ + + void gl_alloc_accum_buffer( GLcontext *ctx ) { @@ -91,7 +94,11 @@ void gl_alloc_accum_buffer( GLcontext *ctx ) /* unable to setup accumulation buffer */ gl_error( ctx, GL_OUT_OF_MEMORY, "glAccum" ); } +#ifdef USE_OPTIMIZED_ACCUM ctx->IntegerAccumMode = GL_TRUE; +#else + ctx->IntegerAccumMode = GL_FALSE; +#endif ctx->IntegerAccumScaler = 0.0; } @@ -118,12 +125,12 @@ void gl_ClearAccum( GLcontext *ctx, static void rescale_accum( GLcontext *ctx ) { const GLuint n = ctx->Buffer->Width * ctx->Buffer->Height * 4; - const GLfloat s = ctx->IntegerAccumScaler * (32767.0 / 255.0); + const GLfloat fChanMax = (1 << (sizeof(GLchan) * 8)) - 1; + const GLfloat s = ctx->IntegerAccumScaler * (32767.0 / fChanMax); GLaccum *accum = ctx->Buffer->Accum; GLuint i; assert(ctx->IntegerAccumMode); - assert(sizeof(GLchan) == 1); /* if not true, 255.0 above must be fixed */ assert(accum); for (i = 0; i < n; i++) { @@ -140,6 +147,8 @@ void gl_Accum( GLcontext *ctx, GLenum op, GLfloat value ) GLuint xpos, ypos, width, height, width4; GLfloat acc_scale; GLubyte rgba[MAX_WIDTH][4]; + const GLint iChanMax = (1 << (sizeof(GLchan) * 8)) - 1; + const GLfloat fChanMax = (1 << (sizeof(GLchan) * 8)) - 1; ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glAccum"); @@ -185,7 +194,7 @@ void gl_Accum( GLcontext *ctx, GLenum op, GLfloat value ) { const GLaccum intVal = (GLaccum) (value * acc_scale); GLuint j; - /* May have to leave optimized accum buffer mode */ + /* Leave optimized accum buffer mode */ if (ctx->IntegerAccumMode) rescale_accum(ctx); for (j = 0; j < height; j++) { @@ -202,7 +211,7 @@ void gl_Accum( GLcontext *ctx, GLenum op, GLfloat value ) case GL_MULT: { GLuint j; - /* May have to leave optimized accum buffer mode */ + /* Leave optimized accum buffer mode */ if (ctx->IntegerAccumMode) rescale_accum(ctx); for (j = 0; j < height; j++) { @@ -247,10 +256,10 @@ void gl_Accum( GLcontext *ctx, GLenum op, GLfloat value ) } else { /* scaled integer accum buffer */ - const GLfloat rscale = value * acc_scale / 255.0; - const GLfloat gscale = value * acc_scale / 255.0; - const GLfloat bscale = value * acc_scale / 255.0; - const GLfloat ascale = value * acc_scale / 255.0; + const GLfloat rscale = value * acc_scale / fChanMax; + const GLfloat gscale = value * acc_scale / fChanMax; + const GLfloat bscale = value * acc_scale / fChanMax; + const GLfloat ascale = value * acc_scale / fChanMax; GLuint j; for (j=0;jBuffer->Accum + ypos * width4 + xpos * 4; @@ -273,7 +282,11 @@ void gl_Accum( GLcontext *ctx, GLenum op, GLfloat value ) /* This is a change to go into optimized accum buffer mode */ if (value > 0.0 && value <= 1.0) { +#ifdef USE_OPTIMIZED_ACCUM ctx->IntegerAccumMode = GL_TRUE; +#else + ctx->IntegerAccumMode = GL_FALSE; +#endif ctx->IntegerAccumScaler = value; } else { @@ -302,19 +315,20 @@ void gl_Accum( GLcontext *ctx, GLenum op, GLfloat value ) } else { /* scaled integer accum buffer */ - const GLfloat rscale = value * acc_scale / 255.0; - const GLfloat gscale = value * acc_scale / 255.0; - const GLfloat bscale = value * acc_scale / 255.0; - const GLfloat ascale = value * acc_scale / 255.0; + const GLfloat rscale = value * acc_scale / fChanMax; + const GLfloat gscale = value * acc_scale / fChanMax; + const GLfloat bscale = value * acc_scale / fChanMax; + const GLfloat ascale = value * acc_scale / fChanMax; + const GLfloat d = 3.0 / acc_scale; GLuint i, j; for (j = 0; j < height; j++) { GLaccum *acc = ctx->Buffer->Accum + ypos * width4 + xpos * 4; gl_read_rgba_span(ctx, width, xpos, ypos, rgba); for (i=0;iIntegerAccumMode) { /* build lookup table to avoid integer divides */ - GLint divisor = (GLint) ((1.0F / ctx->IntegerAccumScaler) + 0.5F); + GLfloat divisor = 1.0F / ctx->IntegerAccumScaler; static GLubyte divTable[32768]; - static GLint prevDivisor = 0.0; + static GLfloat prevDivisor = 0.0; GLuint j; if (divisor != prevDivisor) { assert(divisor * 256 <= 32768); for (j = 0; j < divisor * 256; j++) - divTable[j] = j / divisor; + divTable[j] = (GLint) ((GLfloat) j / divisor + 0.5F); prevDivisor = divisor; } @@ -364,10 +378,10 @@ void gl_Accum( GLcontext *ctx, GLenum op, GLfloat value ) } } else { - const GLfloat rscale = value / acc_scale * 255.0F; - const GLfloat gscale = value / acc_scale * 255.0F; - const GLfloat bscale = value / acc_scale * 255.0F; - const GLfloat ascale = value / acc_scale * 255.0F; + const GLfloat rscale = value / acc_scale * fChanMax; + const GLfloat gscale = value / acc_scale * fChanMax; + const GLfloat bscale = value / acc_scale * fChanMax; + const GLfloat ascale = value / acc_scale * fChanMax; GLuint i, j; for (j=0;jBuffer->Accum + ypos * width4 + xpos*4; @@ -377,10 +391,10 @@ void gl_Accum( GLcontext *ctx, GLenum op, GLfloat value ) g = (GLint) ( (GLfloat) (*acc++) * gscale + 0.5F ); b = (GLint) ( (GLfloat) (*acc++) * bscale + 0.5F ); a = (GLint) ( (GLfloat) (*acc++) * ascale + 0.5F ); - rgba[i][RCOMP] = CLAMP( r, 0, 255 ); - rgba[i][GCOMP] = CLAMP( g, 0, 255 ); - rgba[i][BCOMP] = CLAMP( b, 0, 255 ); - rgba[i][ACOMP] = CLAMP( a, 0, 255 ); + rgba[i][RCOMP] = CLAMP( r, 0, iChanMax ); + rgba[i][GCOMP] = CLAMP( g, 0, iChanMax ); + rgba[i][BCOMP] = CLAMP( b, 0, iChanMax ); + rgba[i][ACOMP] = CLAMP( a, 0, iChanMax ); } if (ctx->Color.SWmasking) { gl_mask_rgba_span( ctx, width, xpos, ypos, rgba ); @@ -491,7 +505,11 @@ void gl_clear_accum_buffer( GLcontext *ctx ) /* update optimized accum state vars */ if (ctx->Accum.ClearColor[0] == 0.0 && ctx->Accum.ClearColor[1] == 0.0 && ctx->Accum.ClearColor[2] == 0.0 && ctx->Accum.ClearColor[3] == 0.0) { +#ifdef USE_OPTIMIZED_ACCUM ctx->IntegerAccumMode = GL_TRUE; +#else + ctx->IntegerAccumMode = GL_FALSE; +#endif ctx->IntegerAccumScaler = 0.0; /* denotes empty accum buffer */ } else { -- cgit v1.2.3