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-rw-r--r--opengl/libagl/vertex.cpp247
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diff --git a/opengl/libagl/vertex.cpp b/opengl/libagl/vertex.cpp
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+/* libs/opengles/vertex.cpp
+**
+** Copyright 2006, The Android Open Source Project
+**
+** Licensed under the Apache License, Version 2.0 (the "License");
+** you may not use this file except in compliance with the License.
+** You may obtain a copy of the License at
+**
+** http://www.apache.org/licenses/LICENSE-2.0
+**
+** Unless required by applicable law or agreed to in writing, software
+** distributed under the License is distributed on an "AS IS" BASIS,
+** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+** See the License for the specific language governing permissions and
+** limitations under the License.
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include "context.h"
+#include "fp.h"
+#include "vertex.h"
+#include "state.h"
+#include "matrix.h"
+
+namespace android {
+
+// ----------------------------------------------------------------------------
+
+void ogles_init_vertex(ogles_context_t* c)
+{
+ c->cull.enable = GL_FALSE;
+ c->cull.cullFace = GL_BACK;
+ c->cull.frontFace = GL_CCW;
+
+ c->current.color.r = 0x10000;
+ c->current.color.g = 0x10000;
+ c->current.color.b = 0x10000;
+ c->current.color.a = 0x10000;
+
+ c->currentNormal.z = 0x10000;
+}
+
+void ogles_uninit_vertex(ogles_context_t* c)
+{
+}
+
+// ----------------------------------------------------------------------------
+// vertex processing
+// ----------------------------------------------------------------------------
+
+// Divides a vertex clip coordinates by W
+static inline
+void perspective(ogles_context_t* c, vertex_t* v, uint32_t enables)
+{
+ // [x,y,z]window = vpt * ([x,y,z]clip / clip.w)
+ // [w]window = 1/w
+
+ // With a regular projection generated by glFrustum(),
+ // we have w=-z, therefore, w is in [zNear, zFar].
+ // Also, zNear and zFar are stricly positive,
+ // and 1/w (window.w) is in [1/zFar, 1/zNear], usually this
+ // means ]0, +inf[ -- however, it is always recommended
+ // to use as large values as possible for zNear.
+ // All in all, w is usually smaller than 1.0 (assuming
+ // zNear is at least 1.0); and even if zNear is smaller than 1.0
+ // values of w won't be too big.
+
+ const int32_t rw = gglRecip28(v->clip.w);
+ const GLfixed* const m = c->transforms.vpt.transform.matrix.m;
+ v->window.w = rw;
+ v->window.x = gglMulAddx(gglMulx(v->clip.x, rw, 16), m[ 0], m[12], 28);
+ v->window.y = gglMulAddx(gglMulx(v->clip.y, rw, 16), m[ 5], m[13], 28);
+ v->window.x = TRI_FROM_FIXED(v->window.x);
+ v->window.y = TRI_FROM_FIXED(v->window.y);
+ if (enables & GGL_ENABLE_DEPTH_TEST) {
+ v->window.z = gglMulAddx(gglMulx(v->clip.z, rw, 16), m[10], m[14], 28);
+ }
+}
+
+// frustum clipping and W-divide
+static inline
+void clipFrustumPerspective(ogles_context_t* c, vertex_t* v, uint32_t enables)
+{
+ // ndc = clip / W
+ // window = ncd * viewport
+
+ // clip to the view-volume
+ uint32_t clip = v->flags & vertex_t::CLIP_ALL;
+ const GLfixed w = v->clip.w;
+ if (v->clip.x < -w) clip |= vertex_t::CLIP_L;
+ if (v->clip.x > w) clip |= vertex_t::CLIP_R;
+ if (v->clip.y < -w) clip |= vertex_t::CLIP_B;
+ if (v->clip.y > w) clip |= vertex_t::CLIP_T;
+ if (v->clip.z < -w) clip |= vertex_t::CLIP_N;
+ if (v->clip.z > w) clip |= vertex_t::CLIP_F;
+
+ v->flags |= clip;
+ c->arrays.cull &= clip;
+
+ if (ggl_likely(!clip)) {
+ // if the vertice is clipped, we don't do the perspective
+ // divide, since we don't need its window coordinates.
+ perspective(c, v, enables);
+ }
+}
+
+// frustum clipping, user clipping and W-divide
+static inline
+void clipAllPerspective(ogles_context_t* c, vertex_t* v, uint32_t enables)
+{
+ // compute eye coordinates
+ c->arrays.mv_transform(
+ &c->transforms.modelview.transform, &v->eye, &v->obj);
+ v->flags |= vertex_t::EYE;
+
+ // clip this vertex against each user clip plane
+ uint32_t clip = 0;
+ int planes = c->clipPlanes.enable;
+ while (planes) {
+ const int i = 31 - gglClz(planes);
+ planes &= ~(1<<i);
+ // XXX: we should have a special dot() for 2,3,4 coords vertices
+ GLfixed d = dot4(c->clipPlanes.plane[i].equation.v, v->eye.v);
+ if (d < 0) {
+ clip |= 0x100<<i;
+ }
+ }
+ v->flags |= clip;
+
+ clipFrustumPerspective(c, v, enables);
+}
+
+// ----------------------------------------------------------------------------
+
+void ogles_vertex_project(ogles_context_t* c, vertex_t* v) {
+ perspective(c, v, c->rasterizer.state.enables);
+}
+
+void ogles_vertex_perspective2D(ogles_context_t* c, vertex_t* v)
+{
+ // here we assume w=1.0 and the viewport transformation
+ // has been applied already.
+ c->arrays.cull = 0;
+ v->window.x = TRI_FROM_FIXED(v->clip.x);
+ v->window.y = TRI_FROM_FIXED(v->clip.y);
+ v->window.z = v->clip.z;
+ v->window.w = v->clip.w << 12;
+}
+
+void ogles_vertex_perspective3DZ(ogles_context_t* c, vertex_t* v) {
+ clipFrustumPerspective(c, v, GGL_ENABLE_DEPTH_TEST);
+}
+void ogles_vertex_perspective3D(ogles_context_t* c, vertex_t* v) {
+ clipFrustumPerspective(c, v, 0);
+}
+void ogles_vertex_clipAllPerspective3DZ(ogles_context_t* c, vertex_t* v) {
+ clipAllPerspective(c, v, GGL_ENABLE_DEPTH_TEST);
+}
+void ogles_vertex_clipAllPerspective3D(ogles_context_t* c, vertex_t* v) {
+ clipAllPerspective(c, v, 0);
+}
+
+static void clipPlanex(GLenum plane, const GLfixed* equ, ogles_context_t* c)
+{
+ const int p = plane - GL_CLIP_PLANE0;
+ if (ggl_unlikely(uint32_t(p) > (GL_CLIP_PLANE5 - GL_CLIP_PLANE0))) {
+ ogles_error(c, GL_INVALID_ENUM);
+ return;
+ }
+
+ vec4_t& equation = c->clipPlanes.plane[p].equation;
+ memcpy(equation.v, equ, sizeof(vec4_t));
+
+ ogles_validate_transform(c, transform_state_t::MVIT);
+ transform_t& mvit = c->transforms.mvit4;
+ mvit.point4(&mvit, &equation, &equation);
+}
+
+// ----------------------------------------------------------------------------
+}; // namespace android
+// ----------------------------------------------------------------------------
+
+using namespace android;
+
+
+void glColor4f(GLfloat r, GLfloat g, GLfloat b, GLfloat a)
+{
+ ogles_context_t* c = ogles_context_t::get();
+ c->current.color.r = gglFloatToFixed(r);
+ c->currentColorClamped.r = gglClampx(c->current.color.r);
+ c->current.color.g = gglFloatToFixed(g);
+ c->currentColorClamped.g = gglClampx(c->current.color.g);
+ c->current.color.b = gglFloatToFixed(b);
+ c->currentColorClamped.b = gglClampx(c->current.color.b);
+ c->current.color.a = gglFloatToFixed(a);
+ c->currentColorClamped.a = gglClampx(c->current.color.a);
+}
+
+void glColor4x(GLfixed r, GLfixed g, GLfixed b, GLfixed a)
+{
+ ogles_context_t* c = ogles_context_t::get();
+ c->current.color.r = r;
+ c->current.color.g = g;
+ c->current.color.b = b;
+ c->current.color.a = a;
+ c->currentColorClamped.r = gglClampx(r);
+ c->currentColorClamped.g = gglClampx(g);
+ c->currentColorClamped.b = gglClampx(b);
+ c->currentColorClamped.a = gglClampx(a);
+}
+
+void glNormal3f(GLfloat x, GLfloat y, GLfloat z)
+{
+ ogles_context_t* c = ogles_context_t::get();
+ c->currentNormal.x = gglFloatToFixed(x);
+ c->currentNormal.y = gglFloatToFixed(y);
+ c->currentNormal.z = gglFloatToFixed(z);
+}
+
+void glNormal3x(GLfixed x, GLfixed y, GLfixed z)
+{
+ ogles_context_t* c = ogles_context_t::get();
+ c->currentNormal.x = x;
+ c->currentNormal.y = y;
+ c->currentNormal.z = z;
+}
+
+// ----------------------------------------------------------------------------
+
+void glClipPlanef(GLenum plane, const GLfloat* equ)
+{
+ const GLfixed equx[4] = {
+ gglFloatToFixed(equ[0]),
+ gglFloatToFixed(equ[1]),
+ gglFloatToFixed(equ[2]),
+ gglFloatToFixed(equ[3])
+ };
+ ogles_context_t* c = ogles_context_t::get();
+ clipPlanex(plane, equx, c);
+}
+
+void glClipPlanex(GLenum plane, const GLfixed* equ)
+{
+ ogles_context_t* c = ogles_context_t::get();
+ clipPlanex(plane, equ, c);
+}
generated by cgit v1.1 at 2024-05-25 18:14:51 +0000